Pro*COBOL Precompiler Programmer's Guide
Release 8.1.5

A68023-01

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F
Embedded SQL Statements and Precompiler Directives

This appendix contains descriptions of both SQL92 embedded SQL statements and directives as well as the Oracle8i embedded SQL extensions. These statements and directives are prefaced in your source code with the keywords, EXEC SQL.

Note: Only statements which differ in syntax from non-embedded SQL are described in this appendix. For details of the non-embedded SQL statements, see the Oracle8i SQL Reference.

This appendix contains the following sections:

Summary of Precompiler Directives and Embedded SQL Statements

Embedded SQL statements place DDL, DML, and Transaction Control statements within a procedural language program. Embedded SQL is supported by the Oracle Precompilers. Table F-1 provides a functional summary of the embedded SQL statements and directives.

The type column in Table F-1 is displayed in the format, source/type, where:

source   Is either SQL92 standard SQL (S) or an Oracle extension (O).  
type   Is either an executable (E) statement or a directive (D).  
Table F-1 Precompiler Directives and Embedded SQL Statements and Clauses
EXEC SQL Statement  Source/Type  Purpose 

ALLOCATE  

O/E  

To allocate memory for a cursor variable.  

ALLOCATE DESCRIPTOR  

S/E  

To allocate a descriptor for ANSI dynamic SQL.  

CALL  

S/E  

Call a stored procedure.  

CLOSE  

S/E  

To disable a cursor, releasing the resources it holds.  

COMMIT  

S/E  

To make all database changes permanent.  

CONNECT  

O/E  

To log on to a database instance.  

CONTEXT ALLOCATE  

O/E  

To allocate memory for a SQLLIB runtime context.  

CONTEXT FREE  

O/E  

To free memory for a SQLLIB runtime context.  

CONTEXT USE  

O/E  

To specify a SQLLIB runtime context.  

DEALLOCATE DESCRIPTOR  

S/E  

To deallocate a descriptor area to free memory.  

DECLARE CURSOR  

S/D  

To declare a cursor, associating it with a query.  

DECLARE DATABASE  

O/D  

To declare an identifier for a non-default database to be accessed in subsequent embedded SQL statements.  

DECLARE STATEMENT  

S/D  

To assign a SQL variable name to a SQL statement.  

DECLARE TABLE  

O/D  

To declare the table structure for semantic checking of embedded SQL statements by the Oracle Precompiler.  

DELETE  

S/E  

To remove rows from a table or from a view's base table.  

DESCRIBE  

S/E  

To initialize a descriptor, a structure holding host variable descriptions.  

DESCRIBE DECRIPTOR  

S/E  

To obtain information about an ANSI SQL statement, and store it in a descriptor.  

EXECUTE...END-EXEC  

O/E  

To execute an anonymous PL/SQL block.  

EXECUTE  

S/E  

To execute a prepared dynamic SQL statement.  

EXECUTE DESCRIPTOR  

S/E  

To execute a prepared statement using ANSI Dynamic SQL.  

EXECUTE IMMEDIATE  

S/E  

To prepare and execute a SQL statement with no host variables.  

FETCH  

S/E  

To retrieve rows selected by a query.  

FETCH DESCRIPTOR  

S/E  

To retrieve rows selected by a query using ANSI Dynamic SQL.  

FREE  

S/E  

To free memory used by a cursor.  

GET DESCRIPTOR  

S/E  

To move information from an ANSI SQL descriptor area into host variables.  

INSERT  

S/E  

To add rows to a table or to a view's base table.  

LOB APPEND  

O/E  

To append a LOB to the end of another lOB.  

LOB ASSIGN  

O/E  

To assign a LOB or BFILE locator to another locator.  

LOB CLOSE  

O/E  

To close an open LOB or BFILE.  

LOB COPY  

O/E  

To copy all or part of a LOB value into another LOB.  

LOB CREATE TEMPORARY  

O/E  

To create a temporary LOB.  

LOB DESCRIBE  

O/E  

To retrieve attributes from a LOB.  

LOB DISABLE BUFFERING  

O/E  

To disable LOB buffering.  

LOB ENABLE BUFFERING  

O/E  

To enable LOB buffering.  

LOB ERASE  

O/E  

To erase a given amount of LOB data starting from a given offset.  

LOB FILE CLOSE ALL  

O/E  

To close all open BFILE.  

LOB FILE SET  

O/E  

To set DIRECTORY and FILENAME in a BFILE locator.  

LOB FLUSH BUFFER  

O/E  

To write the LOB buffers to the database server.  

LOB FREE TEMPORARY  

O/E  

To free temporary space for the LOB locator.  

LOB LOAD  

O/E  

To copy all or part of a BFILE into an internal LOB.  

LOB OPEN  

O/E  

To open a LOB or BFILE to read or read/write access.  

LOB READ  

O/E  

To read all or part of a LOB or BFILE into a buffer.  

LOB TRIM  

O/E  

To truncate a lob value.  

LOB WRITE  

O/E  

To write the contents of a buffer to a LOB.  

OPEN  

S/E  

To execute the query associated with a cursor.  

OPEN DESCRIPTOR  

S/E  

To execute the query associated with a cursor in ANSI Dynamic SQL.  

PREPARE  

S/E  

To parse a dynamic SQL statement.  

ROLLBACK  

S/E  

To end the current transaction and discard all changes.  

SAVEPOINT  

S/E  

To identify a point in a transaction to which you can later roll back.  

SELECT  

S/E  

To retrieve data from one or more tables, views, or snapshots, assigning the selected values to host variables.  

SET DESCRIPTOR  

S/E  

To set information in the ANSI SQL descriptor area from host variables.  

UPDATE  

S/E  

To change existing values in a table or in a view's base table.  

VAR  

O/D  

To override the default datatype and assign a specific Oracle8i external datatype to a host variable.  

WHENEVER  

S/D  

To specify handling for error and warning conditions.  

About the Statement Descriptions

The directives, and statements appear alphabetically. The description of each contains the following sections:

Purpose  

Describes the basic uses of the statement.  

Prerequisites  

Lists privileges you must have and steps that you must take before using the statement. Unless otherwise noted, most statements also require that the database be open by your instance.  

Syntax  

Shows the syntax diagram with the keywords and parameters of the statement.  

Keywords and Parameters  

Describes the purpose of each keyword and parameter.  

Usage Notes  

Discusses how and when to use the statement.  

Examples  

Shows example statements of the statement.  

Related Topics  

Lists related statements, clauses, and sections of this manual.  

How to Read Syntax Diagrams

Syntax diagrams are used to illustrate embedded SQL syntax. They are drawings that depict valid syntax.

Trace each diagram from left to right, in the direction shown by the arrows.

Statements keywords appear in UPPER CASE inside rectangles. Type them exactly as shown in the rectangles. Parameters appear in lower case inside ovals. Variables are used for the parameters. Operators, delimiters, and terminators appear inside circles.

If the syntax diagram has more than one path, you can choose any path to travel.

If you have the choice of more than one keyword, operator, or parameter, your options appear in a vertical list. In the following example, you can travel down the vertical line as far as you like, then continue along any horizontal line:


According to the diagram, all of the following statements are valid:

EXEC SQL WHENEVER NOT FOUND ... 
EXEC SQL WHENEVER SQLERROR ... 
EXEC SQL WHENEVER SQLWARNING ... 

Statement Terminator

In all Pro*COBOL EXEC SQL diagrams, each statement is understood to end with the token END-EXEC.

Required Keywords and Parameters

Required keywords and parameters can appear singly or in a vertical list of alternatives. Single required keywords and parameters appear on the main path, that is, on the horizontal line you are currently traveling. In the following example, cursor is a required parameter:


If there is a cursor named EMPCURSOR, then, according to the diagram, the following statement is valid:

     EXEC SQL CLOSE EMPCURSOR END-EXEC. 

If any of the keywords or parameters in a vertical list appears on the main path, one of them is required. That is, you must choose one of the keywords or parameters, but not necessarily the one that appears on the main path. In the following example, you must choose one of the four actions:


Optional Keywords and Parameters

If keywords and parameters appear in a vertical list above the main path, they are optional. In the following example, instead of traveling down a vertical line, you can continue along the main path:


If there is a database named oracle2, then, according to the diagram, all of the following statements are valid:

     EXEC SQL ROLLBACK END-EXEC. 
     EXEC SQL ROLLBACK WORK END-EXEC. 
     EXEC SQL AT ORACLE2 ROLLBACK END-EXEC. 

Syntax Loops

Loops let you repeat the syntax within them as many times as you like. In the following example, column_name is inside a loop. So, after choosing one column name, you can go back repeatedly to choose another.


If DEBIT, CREDIT, and BALANCE are column names, then, according to the diagram, all of the following statements are valid:

EXEC SQL SELECT DEBIT INTO ... 
EXEC SQL SELECT CREDIT, BALANCE INTO ... 
EXEC SQL SELECT DEBIT, CREDIT, BALANCE INTO ... 

Multi-part Diagrams

Read a multi-part diagram as if all the main paths were joined end-to-end. The following example is a two-part diagram:


According to the diagram, the following statement is valid:

     EXEC SQL PREPARE statement_name FROM :host_string END-EXEC. 

Database Objects

The names of Oracle identifiers, such as tables and columns, must not exceed 30 characters in length. The first character must be a letter, but the rest can be any combination of letters, numerals, dollar signs ($), pound signs (#), and underscores (_).

However, if an Oracle identifier is enclosed by quotation marks ("), it can contain any combination of legal characters, including spaces but excluding quotation marks.

Oracle identifiers are not case-sensitive except when enclosed by quotation marks.

ALLOCATE (Executable Embedded SQL Extension)

Purpose

To allocate a cursor variable to be referenced in a PL/SQL block.

Prerequisites

A cursor variable (see Chapter 6, "Embedded PL/SQL") of type SQL-CURSOR must be declared before allocating memory for the cursor variable.

Syntax


Keywords and Parameters

db_name  

A null-terminated string containing the database connection name, as established previously in a CONNECT statement. If it is omitted, or if it is an empty string, the default database connection is assumed.  

cursor_variable  

A cursor variable of type SQL-CURSOR.  

host_ptr  

A variable of type SQL-ROWID for a ROWID, or SQL-BLOB, SQL-CLOB, or SQL-NCLOB for a LOB.  

Usage Notes

Whereas a cursor is static, a cursor variable is dynamic because it is not tied to a specific query. You can open a cursor variable for any type-compatible query.

For more information on this statement, see PL/SQL User's Guide and Reference and Oracle8i SQL Reference.

Example

This partial example illustrates the use of the ALLOCATE statement:

       ...
 01  EMP-CUR       SQL-CURSOR.
 01  EMP-REC.
     ...
     EXEC SQL ALLOCATE :EMP-CUR END-EXEC.
     ...

Related Topics

CLOSE (Executable Embedded SQL).

EXECUTE (Executable Embedded SQL).

FETCH (Executable Embedded SQL).

FREE (Executable Embedded SQL Extension).

ALLOCATE DESCRIPTOR (Executable Embedded SQL)

Purpose

An ANSI dynamic SQL statement that allocates a descriptor.

Prerequisites

None.

Syntax


Keywords and Parameters

array_size

integer  

Host variable containing number of rows to be processed.

Number of rows to be processed.  

descriptor_name

descriptor name  

Host variable containing the name of the ANSI descriptor.

Name of the ANSI descriptor.  

GLOBAL | LOCAL  

LOCAL (the default) means file scope, as opposed to GLOBAL, which means application scope.  

WITH MAX integer  

Maximum number of host variables. The default is 100.  

Usage Notes

Use DYNAMIC=ANSI precompiler option. For information on using this statement, see "ALLOCATE DESCRIPTOR".

Example

     EXEC SQL 
       FOR :batch ALLOCATE DESCRIPTOR GLOBAL :binddes WITH MAX 25 
     END-EXEC.

Related Topics

DESCRIBE DESCRIPTOR (Executable Embedded SQL).

GET DESCRIPTOR (Executable Embedded SQL).

SET DESCRIPTOR (Executable Embedded SQL).

CALL (Executable Embedded SQL)

Purpose

To call a stored procedure.

Prerequisites

An active database connection must exist.

Syntax


Keywords and Parameters

schema  

Is the schema containing the procedure. If you omit schema, Oracle8i assumes the procedure is in your own schema.  

pkg  

The package where the procedure is stored.  

st_proc  

The stored procedure to be called.  

db_link  

The complete or partial name of a database link to a remote database where the procedure is located. For information on referring to database links, see the Oracle8 SQL Reference.  

expr  

The list of expressions that are the parameters of the procedure.  

ret_var  

The host variable that receives the returned value of a function.  

ret_ind  

The indicator variable for ret_var.  

Usage Notes

For more about this statement, see Calling a Stored PL/SQL or Java Subprogram.

For a complete discussion of stored procedures, see Oracle8i Application Developer's Guide - Fundamentals, "External Routines" chapter.

Example

 ...
     05  EMP-NAME      PIC X(10) VARYING.
     05  EMP-NUMBER    PIC S9(4) COMP VALUE ZERO.
     05  SALARY        PIC S9(5)V99 COMP-3 VALUE ZERO.
...
      05  D-EMP-NUMBER  PIC 9(4).
...
      ACCEPT D-EMP-NUMBER.
      EXEC SQL 
        CALL mypkge.getsal(:EMP-NUMBER, :D-EMP-NUMBER, :EMP-NAME) INTO :SALARY 
      END-EXEC.
...

Related Topics

None

CLOSE (Executable Embedded SQL)

Purpose

To disable a cursor, freeing the resources acquired by opening the cursor, and releasing parse locks.

Prerequisites

The cursor or cursor variable must be open and MODE=ANSI.

Syntax


Keywords and Parameters

cursor  

The cursor to be closed.  

cusor_variable  

The cursor variable to be closed.  

Usage Notes

Rows cannot be fetched from a closed cursor. A cursor need not be closed to be reopened. The HOLD_CURSOR and RELEASE_CURSOR precompiler options alter the effect of the CLOSE statement. For information on these options, see Chapter 14, "Precompiler Options".

Example

This example illustrates the use of the CLOSE statement:

     EXEC SQL CLOSE EMP-CUR END-EXEC.

Related Topics

DECLARE CURSOR (Embedded SQL Directive).

OPEN (Executable Embedded SQL).

PREPARE (Executable Embedded SQL).

COMMIT (Executable Embedded SQL)

Purpose

To end your current transaction, making permanent all its changes to the database and optionally freeing all resources and disconnecting from the database server.

Prerequisites

To commit your current transaction, no privileges are necessary.

To manually commit a distributed in-doubt transaction that you originally committed, you must have FORCE TRANSACTION system privilege. To manually commit a distributed in-doubt transaction that was originally committed by another user, you must have FORCE ANY TRANSACTION system privilege.

Syntax


Keyword and Parameters

AT  

Identifies the database to which the COMMIT statement is issued. The database can be identified by either:  

 

db_name  

A database identifier declared in a previous DECLARE DATABASE statement or used in a CONNECT statement.  

 

host_variable  

A host variable whose value is a previously declared db_name.  

 

If you omit this clause, Oracle8i issues the statement to your default database.  

WORK  

Is supported only for compliance with standard SQL. The statements COMMIT and COMMIT WORK are equivalent.  

COMMENT  

Specifies a comment to be associated with the current transaction. The 'text' is a quoted literal of up to 50 characters that Oracle8i stores in the data dictionary view DBA_2PC_PENDING along with the transaction ID if the transaction becomes in-doubt.  

RELEASE  

Frees all resources and disconnects the application from the Oracle8i Server.  

FORCE  

Manually commits an in-doubt distributed transaction. The transaction is identified by the 'text' containing its local or global transaction ID. To find the IDs of such transactions, query the data dictionary view DBA_2PC_PENDING. You can also use the optional integer to explicitly assign the transaction a system change number (SCN). If you omit the integer, the transaction is committed using the current SCN.  

Usage Notes

Always explicitly commit or rollback the last transaction in your program by using the COMMIT or ROLLBACK statement and the RELEASE option. Oracle8i automatically rolls back changes if the program terminates abnormally.

The COMMIT statement has no effect on host variables or on the flow of control in the program. For more information on this statement, see "Using the COMMIT Statement".

Example

This example illustrates the use of the embedded SQL COMMIT statement:

     EXEC SQL AT SALESDB COMMIT RELEASE END-EXEC.

Related Topics

ROLLBACK (Executable Embedded SQL).

SAVEPOINT (Executable Embedded SQL).

CONNECT (Executable Embedded SQL Extension)

Purpose

To logon to an Oracle8i database.

Prerequisites

You must have CREATE SESSION system privilege in the specified database.

Syntax


Keyword and Parameters

user

password  

Specifies your username and password separately.  

user_password  

Is a single host variable containing the Oracle8i username and password separated by a slash (/).

To allow Oracle8i to verify your connection through your operating system, specify "/" as the :user_password value. To allow Oracle8i to verify your connection through your operating system, specify "/" as the :user_password value.  

AT  

Identifies the database to which the connection is made. The database can be identified by either:  

 

db_name  

A database identifier declared in a previous DECLARE DATABASE statement.  

 

host_variable  

A host variable whose value is a previously declared db_name.  

USING  

Specifies the Net8 database specification string used to connect to a non-default database. If you omit this clause, you are connected to your default database.  

ALTER AUTHORIZATION  

Change password to the following string.  

new_password  

New password string.  

IN SYSDBA MODE

IN SYSOPER MODE  

Connect with SYSDBA or SYSOPER system privileges. Not allowed when ALTER AUTHORIZATION is used, or precompiler option AUTO_CONNECT is set to YES.  

Usage Notes

A program can have multiple connections, but can only connect once to your default database. For more information on this statement, see "Advanced Connection Options".

Example

The following example illustrate the use of CONNECT:

     EXEC SQL CONNECT :USERNAME 
          IDENTIFIED BY :PASSWORD 
     END-EXEC.

You can also use this statement in which the value of :userid is the value of :username and :password separated by a "/" such as 'SCOTT/TIGER':

     EXEC SQL CONNECT :USERID END-EXEC.

Related Topics

COMMIT (Executable Embedded SQL).

DECLARE DATABASE (Oracle Embedded SQL Directive).

ROLLBACK (Executable Embedded SQL).

CONTEXT ALLOCATE (Executable Embedded SQL Extension)

Purpose

To initialize a SQLLIB runtime context that is referenced in an EXEC SQL CONTEXT USE statement.

Prerequisites

The runtime context must be declared of type SQL-CONTEXT.

Syntax


Keywords and Parameters

context  

The SQLLIB runtime context for which memory is to be allocated.  

Usage Notes

For more information on this statement, see "User-Specified Runtime Contexts".

Example

This example illustrates the use of a CONTEXT ALLOCATE statement in a Pro*C/C++ embedded SQL program:

     EXEC SQL CONTEXT ALLOCATE :ctx1 END-EXEC.

Related Topics

CONTEXT FREE (Executable Embedded SQL Extension).

CONTEXT USE (Oracle Embedded SQL Directive).

CONTEXT FREE (Executable Embedded SQL Extension)

Purpose

To free all memory associated with a runtime context and place a null pointer in the host program variable.

Prerequisites

The CONTEXT ALLOCATE statement must be used to allocate memory for the specified runtime context before the CONTEXT FREE statement can free the memory allocated for it.

Syntax


Keywords and Parameters

context  

The allocated runtime context for which the memory is to be deallocated.  

Usage Notes

For more information on this statement, see "User-Specified Runtime Contexts".

Example

This example illustrates the use of a CONTEXT FREE statement in a Pro*C/C++ embedded SQL program:

     EXEC SQL CONTEXT FREE :ctx1 END-EXEC.

Related Topics

CONTEXT ALLOCATE (Executable Embedded SQL Extension).

CONTEXT USE (Oracle Embedded SQL Directive).

CONTEXT USE (Oracle Embedded SQL Directive)

Purpose

To instruct the precompiler to use the specified SQLLIB runtime context on subsequent executable SQL statementsPrerequisites

The runtime context specified by the CONTEXT USE directive must be previously declared.

Syntax


Keywords and Parameters

context  

The allocated runtime context to use for subsequent executable SQL statements that follow it. For example, after specifying in your source code which context to use (multiple contexts can be allocated), you can connect to the Oracle Server and perform database operations within the scope of that context.  

DEFAULT  

Indicates that the global contex is to be used.  

Usage Notes

This statement has no effect on declarative statements such as EXEC SQL INCLUDE or EXEC ORACLE OPTION. It works similarly to the EXEC SQL WHENEVER directive in that it affects all executable SQL statements which positionally follow it in a given source file without regard to standard C scope rules.

For more information on this statement, see "User-Specified Runtime Contexts".

Example

This example illustrates the use of a CONTEXT USE directive in a Pro*C/C++ program:

     EXEC SQL CONTEXT USE :ctx1 END-EXEC. 

Related Topics

CONTEXT ALLOCATE (Executable Embedded SQL Extension).

CONTEXT FREE (Executable Embedded SQL Extension).

DEALLOCATE DESCRIPTOR (Embedded SQL Statement)

Purpose

An ANSI dynamic SQL statement that deallocates a descriptor area to free memory.

Prerequisites

The descriptor specified by the DEALLOCATE DESCRIPTOR statement must be previously allocated using the ALLOCATE DESCRIPTOR statement.

Syntax


Keywords and Parameters

GLOBAL | LOCAL  

LOCAL (the default) means file scope, as opposed to GLOBAL, which means application scope.  

descriptor_name

'descriptor name'  

Host variable containing the name of the allocated ANSI descriptor.

Name of the allocated ANSI descriptor.  

'

Usage Notes

Use DYNAMIC=ANSI precompiler option.

For more information on this statement, see "DEALLOCATE DESCRIPTOR".

Example

     EXEC SQL DEALLOCATE DESCRIPTOR GLOBAL 'SELDES'  END-EXEC. 

Related Topics

ALLOCATE DESCRIPTOR (Executable Embedded SQL).

DESCRIBE DESCRIPTOR (Executable Embedded SQL).

GET DESCRIPTOR (Executable Embedded SQL).

PREPARE (Executable Embedded SQL).

SET DESCRIPTOR (Executable Embedded SQL).

DECLARE CURSOR (Embedded SQL Directive)

Purpose

To declare a cursor, giving it a name and associating it with a SQL statement or a PL/SQL block.

Prerequisites

If you associate the cursor with an identifier for a SQL statement or PL/SQL block, you must have declared this identifier in a previous DECLARE STATEMENT statement.

Syntax


Keywords and Parameters

AT  

Identifies the database on which the cursor is declared. The database can be identified by either:  

 

db_name  

Database identifier declared in a previous DECLARE DATABASE statement.  

 

host_variable  

Host variable whose value is a previously declared db_name.  

 

If you omit this clause, Oracle8i declares the cursor on your default database.  

cursor  

Name of the cursor to be declared.  

WITH HOLD  

Cursor remains open after a COMMIT or a ROLLBACK. The cursor must not be declared for UPDATE.  

SELECT statement  

Is a SELECT statement to be associated with the cursor. The following statement cannot contain an INTO clause.  

statement_name

 

Identifies a SQL statement or PL/SQL block to be associated with the cursor. The statement_name or block_name must be previously declared in a DECLARE STATEMENT statement.  

Usage Notes

You must declare a cursor before referencing it in other embedded SQL statements. The scope of a cursor declaration is global within its precompilation unit and the name of each cursor must be unique in its scope. You cannot declare two cursors with the same name in a single precompilation unit.

You can reference the cursor in the WHERE clause of an UPDATE or DELETE statement using the CURRENT OF syntax, provided that the cursor has been opened with an OPEN statement and positioned on a row with a FETCH statement. For more information on this statement, see "WITH HOLD Clause in DECLARE CURSOR Statements".

Example

This example illustrates the use of a DECLARE CURSOR statement:

     EXEC SQL DECLARE EMPCURSOR CURSOR 
         FOR SELECT ENAME, EMPNO, JOB, SAL 
         FROM EMP 
         WHERE DEPTNO = :DEPTNO 
         FOR UPDATE OF SAL 
     END-EXEC.

Related Topics

CLOSE (Executable Embedded SQL).

DECLARE DATABASE (Oracle Embedded SQL Directive).

DECLARE STATEMENT (Embedded SQL Directive).

DELETE (Executable Embedded SQL).

FETCH (Executable Embedded SQL).

OPEN (Executable Embedded SQL).

PREPARE (Executable Embedded SQL).

SELECT (Executable Embedded SQL).

UPDATE (Executable Embedded SQL).

DECLARE DATABASE (Oracle Embedded SQL Directive)

Purpose

To declare an identifier for a non-default database to be accessed in subsequent embedded SQL statements.

Prerequisites

You must have access to a username on the non-default database.

Syntax


Keywords and Parameters

db_name  

The identifier established for the non-default database.  

Usage Notes

You declare a db_name for a non-default database so that other embedded SQL statements can refer to that database using the AT clause. Before issuing a CONNECT statement with an AT clause, you must declare a db_name for the non-default database with a DECLARE DATABASE statement.

For more information on this statement, see "Using Username/Password".

Example

This example illustrates the use of a DECLARE DATABASE directive:

     EXEC SQL DECLARE ORACLE3 DATABASE END-EXEC.

Related Topics

COMMIT (Executable Embedded SQL)

CONNECT (Executable Embedded SQL Extension).

DECLARE CURSOR (Embedded SQL Directive).

DECLARE STATEMENT (Embedded SQL Directive).

DELETE (Executable Embedded SQL).

EXECUTE (Executable Embedded SQL).

EXECUTE IMMEDIATE (Executable Embedded SQL).

INSERT (Executable Embedded SQL).

SELECT (Executable Embedded SQL).

UPDATE (Executable Embedded SQL).

DECLARE STATEMENT (Embedded SQL Directive)

Purpose

To declare an identifier for a SQL statement or PL/SQL block to be used in other embedded SQL statements.

Prerequisites

None.

Syntax


Keywords and Parameters


AT  

Identifies the database on which the SQL statement or PL/SQL block is declared. The database can be identified by either:  

 

db_name  

Database identifier declared in a previous DECLARE DATABASE statement.  

 

host_variable  

Host variable whose value is a previously declared db_name.  

 

If you omit this clause, Oracle8i declares the SQL statement or PL/SQL block on your default database.  

statement_name  

Is the declared identifier for the statement or PL/SQL block.  

Usage Notes

You must declare an identifier for a SQL statement or PL/SQL block with a DECLARE STATEMENT statement only if a DECLARE CURSOR statement referencing the identifier appears physically (not logically) in the embedded SQL program before the PREPARE statement that parses the statement or block and associates it with its identifier.

The scope of a statement declaration is global within its precompilation unit, like a cursor declaration. For more information on this statement, see "DECLARE".

Example I

This example illustrates the use of the DECLARE STATEMENT statement:

     EXEC SQL AT REMOTEDB 
         DECLARE MYSTATEMENT STATEMENT 
     END-EXEC.
     EXEC SQL PREPARE MYSTATEMENT FROM :MY-STRING
     END-EXEC.
     EXEC SQL EXECUTE MYSTATEMENT END-EXEC.

Example II

In this example from a Pro*COBOL embedded SQL program, the DECLARE STATEMENT statement is required because the DECLARE CURSOR statement precedes the PREPARE statement:

     EXEC SQL DECLARE MYSTATEMENT STATEMENT END-EXEC. 
     EXEC SQL DECLARE EMPCURSOR CURSOR FOR MYSTATEMENT END-EXEC. 
     EXEC SQL PREPARE MYSTATEMENT FROM :MY-STRING END-EXEC. 
     ...

Related Topics

CLOSE (Executable Embedded SQL).

DECLARE DATABASE (Oracle Embedded SQL Directive).

FETCH (Executable Embedded SQL).

OPEN (Executable Embedded SQL).

PREPARE (Executable Embedded SQL).

DECLARE TABLE (Oracle Embedded SQL Directive)

Purpose

To define the structure of a table or view, including each column's datatype, default value, and NULL or NOT NULL specification for semantic checking by the precompiler when option SQLCHECK=SEMANTICS (or FULL).

Prerequisites

None.

Syntax


Keywords and Parameters

table  

The name of the declared table.  

column  

A column of the table.  

datatype  

The datatype of a column. For information on Oracle8i datatypes, see "The Oracle8i Datatypes".  

NOT NULL  

Specifies that a column cannot contain nulls.  

Usage Notes

Datatypes can only use integers (not expressions) for length, precision, scale. For more information on using this statement, see "Specifying SQLCHECK=SEMANTICS" on page E-3.

Example

The following statement declares the PARTS table with the PARTNO, BIN, and QTY columns:

     EXEC SQL DECLARE PARTS TABLE 
         (PARTNO  NUMBER  NOT NULL, 
          BIN     NUMBER, 
          QTY     NUMBER) 
     END-EXEC.

Related Topics

None.

DELETE (Executable Embedded SQL)

Purpose

To remove rows from a table or from a view's base table.

Prerequisites

For you to delete rows from a table, the table must be in your own schema or you must have DELETE privilege on the table.

For you to delete rows from the base table of a view, the owner of the schema containing the view must have DELETE privilege on the base table. Also, if the view is in a schema other than your own, you must be granted DELETE privilege on the view.

The DELETE ANY TABLE system privilege also allows you to delete rows from any table or any view's base table.

Syntax


where the DML Returning clause is:


Keywords and Parameters

AT  

Identifies the database to which the DELETE statement is issued. The database can be identified by either:  

 

db_name  

A database identifier declared in a previous DECLARE DATABASE statement.  

 

host_variable  

A host variable whose value is a previously declared db_name.  

 

If you omit this clause, the DELETE statement is issued to your default database.  

host_integer

integer  

Limits the number of times the statement is executed if the WHERE clause contains array host variables. If you omit this clause, Oracle8i executes the statement once for each component of the smallest array.  

schema  

The schema containing the table or view. If you omit schema, Oracle8i assumes the table or view is in your own schema.  

table view  

The name of a table from which the rows are to be deleted. If you specify view, Oracle8i deletes rows from the view's base table.  

dblink  

The complete or partial name of a database link to a remote database where the table or view is located. For information on referring to database links, see Chapter 2 of the Oracle8i SQL Reference. You can only delete rows from a remote table or view if you are using Oracle8i with the distributed option.

If you omit dblink, Oracle8 assumes that the table or view is located on the local database.  

part_name  

Name of partition in the table  

alias  

The alias assigned to the table. Aliases are generally used in DELETE statements with correlated queries.  

WHERE  

Specifies which rows are deleted:  

 

condition  

Deletes only rows that satisfy the condition. This condition can contain host variables and optional indicator variables. See the syntax description of condition in the Oracle8i SQL Reference.  

 

CURRENT OF

 

Deletes only the row most recently fetched by the cursor. The cursor cannot be associated with a SELECT statement that performs a join, unless its FOR UPDATE clause specifically locks only one table.  

 

If you omit this clause entirely, Oracle8i deletes all rows from the table or view.  

DML returning clause  

See "DML Returning Clause" for a discussion.  

Usage Notes

The host variables in the WHERE clause must be either all scalars or all arrays. If they are scalars, Oracle8i executes the DELETE statement only once. If they are arrays, Oracle8i executes the statement once for each set of array components. Each execution may delete zero, one, or multiple rows.

Array host variables in the WHERE clause can have different sizes. In this case, the number of times Oracle8i executes the statement is determined by the smaller of the following values:

If no rows satisfy the condition, no rows are deleted and the SQLCODE returns a NOT_FOUND condition.

The cumulative number of rows deleted is returned through the SQLCA. If the WHERE clause contains array host variables, this value reflects the total number of rows deleted for all components of the array processed by the DELETE statement.

If no rows satisfy the condition, Oracle8i returns an error through the SQLCODE of the SQLCA. If you omit the WHERE clause, Oracle8i raises a warning flag in the fifth component of SQLWARN in the SQLCA. For more information on this statement and the SQLCA, see "Using the SQL Communications Area".

You can use comments in a DELETE statement to pass instructions, or hints, to the Oracle8i optimizer. The optimizer uses hints to choose an execution plan for the statement. For more information on hints, see Oracle8i Tuning.

Example

This example illustrates the use of the DELETE statement within a Pro*COBOL program:

     EXEC SQL DELETE FROM EMP
        WHERE DEPTNO = :DEPTNO
        AND JOB = :JOB
    END-EXEC.
    EXEC SQL DECLARE EMPCURSOR CURSOR
        FOR SELECT EMPNO, COMM
        FROM EMP
    END-EXEC.
    EXEC SQL OPEN EMPCURSOR END-EXEC.
    EXEC SQL FETCH EMPCURSOR
        INTO :EMP-NUMBER, :COMMISSION
    END-EXEC.
    EXEC SQL DELETE FROM EMP
        WHERE CURRENT OF EMPCURSOR
    END-EXEC. 

Related Topics

DECLARE DATABASE (Oracle Embedded SQL Directive).

DECLARE STATEMENT (Embedded SQL Directive).

DESCRIBE (Executable Embedded SQL)

Purpose

To initialize a descriptor to hold descriptions of host variables for an Oracle dynamic SQL statement or PL/SQL block.

Prerequisites

You must have prepared the SQL statement or PL/SQL block in a previous embedded SQL PREPARE statement.

Syntax


Keywords and Parameters

BIND VARIABLES FOR  

Initializes the descriptor to hold information about the input variables for the SQL statement or PL/SQL block.  

SELECT LIST FOR  

Initializes the descriptor to hold information about the select list of a SELECT statement.  

 

The default is SELECT LIST FOR.  

statement_name  

Identifies a SQL statement or PL/SQL block previously prepared with a PREPARE statement.  

descriptor  

The name of the descriptor to be initialized.  

Usage Notes

You must issue a DESCRIBE statement before manipulating the bind or select descriptor within an embedded SQL program.

You cannot describe both input variables and output variables into the same descriptor.

The number of variables found by a DESCRIBE statement is the total number of placeholders in the prepare SQL statement or PL/SQL block, rather than the total number of uniquely named placeholders. For more information on this statement, see "The DESCRIBE Statement".

Example

This example illustrates the use of the DESCRIBE statement in a Pro*COBOL embedded SQL program:

     EXEC SQL PREPARE MYSTATEMENT FROM :MY-STRING END-EXEC. 
     EXEC SQL DECLARE EMPCURSOR 
         FOR SELECT EMPNO, ENAME, SAL, COMM 
         FROM EMP 
         WHERE DEPTNO = :DEPT-NUMBER 
     END-EXEC.
     EXEC SQL DESCRIBE BIND VARIABLES FOR MYSTATEMENT 
         INTO BINDDESCRIPTOR
     END-EXEC. 
     EXEC SQL OPEN EMPCURSOR 
         USING BINDDESCRIPTOR
     END-EXEC. 
     EXEC SQL DESCRIBE SELECT LIST FOR MY-STATEMENT 
         INTO SELECTDESCRIPTOR
     END-EXEC. 
     EXEC SQL FETCH EMPCURSOR 
         INTO SELECTDESCRIPTOR
     END-EXEC. 

Related Topics

PREPARE (Executable Embedded SQL).

DESCRIBE DESCRIPTOR (Executable Embedded SQL)

Purpose

Used to obtain information about an ANSI SQL statement, and to store it in a descriptor.

Prerequisites

You must have prepared the SQL statement in a previous embedded SQL PREPARE statement.

Syntax


Keywords and Parameters

statement_id  

The name of the previously prepared SQL statement or PL/SQL block. OUTPUT is the default.  

desc_name  

Host variable containing the name of the descriptor that will hold information about the SQL statement.  

'descriptor name'  

Name of the descriptor  

GLOBAL | LOCAL  

LOCAL is the default. It means file scope, as opposed to GLOBAL, which means application scope.  

Usage Notes

Use DYNAMIC=ANSI precompiler option. Only COUNT and NAME are implemented for the INPUT descriptor.

The number of variables found by a DESCRIBE statement is the total number of place-holders in the prepare SQL statement or PL/SQL block, rather than the total number of uniquely named place-holders. For more information on this statement, see Chapter 13, "Oracle Dynamic SQL".

Example

     EXEC SQL PREPARE s FROM :my_stament END-EXEC. 
     EXEC SQL DESCRIBE INPUT s USING DESCRIPTOR 'in' END-EXEC. 

Related Topics

ALLOCATE DESCRIPTOR (Executable Embedded SQL).

DEALLOCATE DESCRIPTOR (Embedded SQL Statement).

GET DESCRIPTOR (Executable Embedded SQL).

PREPARE (Executable Embedded SQL).

SET DESCRIPTOR (Executable Embedded SQL).

EXECUTE ... END-EXEC (Executable Embedded SQL Extension)

Purpose

To embed an anonymous PL/SQL block into an Oracle Pro*COBOL program.

Prerequisites

None.

Syntax


Keywords and Parameters


AT  

Identifies the database on which the PL/SQL block is executed. The database can be identified by either:  

 

db_name  

A database identifier declared in a previous DECLARE DATABASE statement.  

 

host_variable  

A host variable whose value is a previously declared db_name.  

 

If you omit this clause, the PL/SQL block is executed on your default database.  

pl/sql_block  

For information on PL/SQL, including how to write PL/SQL blocks, see the PL/SQL User's Guide and Reference.  

END-EXEC  

Must appear after the embedded PL/SQL block. The keyword END-EXEC must be followed by the statement terminator for COBOL, ".".  

Usage Notes

Since the Oracle Precompilers treat an embedded PL/SQL block like a single embedded SQL statement, you can embed a PL/SQL block anywhere in an Oracle Precompiler program that you can embed a SQL statement. For more information on embedding PL/SQL blocks in Oracle Precompiler programs, see Chapter 6, "Embedded PL/SQL".

Example

Placing this EXECUTE statement in an Oracle Precompiler program embeds a PL/SQL block in the program:

     EXEC SQL EXECUTE 
     BEGIN 
        SELECT ENAME, JOB, SAL 
            INTO :EMP-NAME:IND-NAME, :JOB-TITLE, :SALARY 
            FROM EMP 
            WHERE EMPNO = :EMP-NUMBER; 
        IF :EMP-NAME:IND-NAME IS NULL 
            THEN RAISE NAME-MISSING; 
        END IF; 
     END; 
     END-EXEC.

Related Topics

EXECUTE IMMEDIATE (Executable Embedded SQL).

EXECUTE (Executable Embedded SQL)

Purpose

In Oracle dynamic SQL, to execute a DELETE, INSERT, or UPDATE statement or a PL/SQL block that has been previously prepared with an embedded SQL PREPARE statement.

Prerequisites

You must first prepare the SQL statement or PL/SQL block with an embedded SQL PREPARE statement.

Syntax


Keywords and Parameters

FOR :array_size

FOR integer  

Host variable containing the number of rows to be processed.

Number of rows to be processed.

Limits the number of times the statement is executed when the USING clause contains array host variables If you omit this clause, Oracle8i executes the statement once for each component of the smallest array.  

statement_id  

A precompiler identifier associated with the SQL statement or PL/SQL block to be executed. Use the embedded SQL PREPARE statement to associate the precompiler identifier with the statement or PL/SQL block.  

USING DESCRIPTOR SQLDA_descriptor  

Uses an Oracle descriptor.

CANNOT be used together with an ANSI descriptor (INTO clause).  

USING  

Specifies a list of host variables with optional indicator variables that Oracle8i substitutes as input variables into the statement to be executed. The host and indicator variables must be either all scalars or all arrays.  

host_variable  

Host variables.  

indicator_variable  

Indicator variables.  

Usage Note

For more information on this statement, see Chapter 9, "Oracle Dynamic SQL".

Example

This example illustrates the use of the EXECUTE statement in a Pro*COBOL embedded SQL program:

     EXEC SQL PREPARE MY-STATEMENT FROM MY-STRING END-EXEC. 
     EXEC SQL EXECUTE MY-STATEMENT USING :MY-VAR END-EXEC. 

Related Topics

DECLARE DATABASE (Oracle Embedded SQL Directive).

PREPARE (Executable Embedded SQL).

EXECUTE DESCRIPTOR (Executable Embedded SQL

Purpose

In ANSI SQL Method 4, to execute a DELETE, INSERT, or UPDATE statement or a PL/SQL block that has been previously prepared with an embedded SQL PREPARE statement.

Prerequisites

You must first prepare the SQL statement or PL/SQL block with an embedded SQL PREPARE statement.

Syntax


Keywords and Parameters

FOR :array_size

FOR integer  

Host variable containing the number of rows to be processed.

Number of rows to be processed.

Limits the number of times the statement is executed. Oracle8i executes the statement once for each component of the smallest array.  

statement_id  

A precompiler identifier associated with the SQL statement or PL/SQL block to be executed. Use the embedded SQL PREPARE statement to associate the precompiler identifier with the statement or PL/SQL block.  

USING

descriptor_name

descriptor name  

An ANSI input descriptor.

Host variable containing name of the input descriptor.

Name of the input descriptor.  

INTO

descriptor_name

descriptor name  

An ANSI output descriptor.

Host variable containing the name of the output descriptor.

Name of the output descriptor.  

GLOBAL | LOCAL  

LOCAL (the default) means file scope, as opposed to GLOBAL, which means application scope.  

Usage Notes

For more information on this statement, see "EXECUTE".

Examples

The ANSI dynamic SQL Method 4 allows DML RETURNING in a SELECT to be supported by the INTO clause in EXECUTE:

EXEC SQL EXECUTE S2 USING DESCRIPTOR :bv1 INTO DESCRIPTOR 'SELDES' END-EXEC.

Related Topics

DECLARE DATABASE (Oracle Embedded SQL Directive).

PREPARE (Executable Embedded SQL).

EXECUTE IMMEDIATE (Executable Embedded SQL)

Purpose

To prepare and execute a DELETE, INSERT, or UPDATE statement or a PL/SQL block containing no host variables.

Prerequisites

None.

Syntax


Keywords and Parameters

AT  

Identifies the database on which the SQL statement or PL/SQL block is executed. The database can be identified by either:  

 

db_name  

A database identifier declared in a previous DECLARE DATABASE statement.  

 

host_variable  

A host variable whose value is a previously declared db_name.  

 

If you omit this clause, the statement or block is executed on your default database.  

host_string  

A host variable whose value is the SQL statement or PL/SQL block to be executed.  

text  

A text literal containing the SQL statement or PL/SQL block to be executed. The quotes may be omitted.  

 

The SQL statement can only be a DELETE, INSERT, or UPDATE statement.  

Usage Notes

When you issue an EXECUTE IMMEDIATE statement, Oracle8i parses the specified SQL statement or PL/SQL block, checking for errors, and executes it. If any errors are encountered, they are returned in the SQLCODE component of the SQLCA.

For more information on this statement, see "The EXECUTE IMMEDIATE Statement".

Example

This example illustrates the use of the EXECUTE IMMEDIATE statement:

     EXEC SQL
         EXECUTE IMMEDIATE 'DELETE FROM EMP WHERE EMPNO = 9460'
     END-EXEC. 

Related Topics

PREPARE (Executable Embedded SQL).

EXECUTE (Executable Embedded SQL).

FETCH (Executable Embedded SQL)

Purpose

In Oracle dynamic SQL, to retrieve one or more rows returned by a query, assigning the select list values to host variables. For ANSI Dynamic SQL Method 4, see "FETCH DESCRIPTOR (Executable Embedded SQL)".

Prerequisites

You must first open the cursor with an the OPEN statement.

Syntax


Keywords and Parameters

FOR :array_sizeFOR integer  

Host variable containing the number of rows to be processed.

Number of rows to be processed.

Limits the number of rows fetched if you are using array host variables. If you omit this clause, Oracle8i fetches enough rows to fill the smallest array.  

cursor  

A cursor that is declared by a DECLARE CURSOR statement. The FETCH statement returns one of the rows selected by the query associated with the cursor.  

cursor_variable  

A cursor variable is allocated an ALLOCATE statement. The FETCH statement returns one of the rows selected by the query associated with the cursor variable.  

INTO  

Specifies a list of host variables and optional indicator variables into which data is fetched. These host variables and indicator variables must be declared within the program.  

USING SQLDA_variable  

Specifies the Oracle descriptor referenced in a previous DESCRIBE statement. Only use this clause with dynamic embedded SQL, method 4. The USING clause does not apply when a cursor variable is used.  

host_variable  

The host variable into which data is returned.  

indicator_variable  

The host indicator variable.  

Usage Notes

The FETCH statement reads the rows of the active set and names the output variables which contain the results. Indicator values are set to -1 if their associated host variable is null. The first FETCH statement for a cursor also sorts the rows of the active set, if necessary.

The number of rows retrieved is specified by the size of the output host variables and the value specified in the FOR clause. The host variables to receive the data must be either all scalars or all arrays. If they are scalars, Oracle8i fetches only one row. If they are arrays, Oracle8i fetches enough rows to fill the arrays.

Array host variables can have different sizes. In this case, the number of rows Oracle8i fetches is determined by the smaller of the following values:

Of course, the number of rows fetched can be further limited by the number of rows that actually satisfy the query.

If a FETCH statement does not retrieve all rows returned by the query, the cursor is positioned on the next returned row. When the last row returned by the query has been retrieved, the next FETCH statement results in an error code returned in the SQLCODE element of the SQLCA.

Note that the FETCH statement does not contain an AT clause. You must specify the database accessed by the cursor in the DECLARE CURSOR statement.

You can only move forward through the active set with FETCH statements. If you want to revisit any of the previously fetched rows, you must reopen the cursor and fetch each row in turn. If you want to change the active set, you must assign new values to the input host variables in the cursor's query and reopen the cursor.

Example

This example illustrates the FETCH statement in a Pro*COBOL embedded SQL program:

     EXEC SQL DECLARE EMPCURSOR CURSOR FOR 
         SELECT JOB, SAL FROM EMP WHERE DEPTNO = 30
     END-EXEC. 
     ... 
     EXEC SQL WHENEVER NOT FOUND GOTO ... 
 LOOP. 
     EXEC SQL FETCH EMPCURSOR INTO :JOB-TITLE1, :SALARY1 END-EXEC. 
     EXEC SQL FETCH EMPCURSOR INTO :JOB-TITLE2, :SALARY2 END-EXEC. 
     ... 
     GO TO LOOP. 
     ... 

Related Topics

CLOSE (Executable Embedded SQL).

DECLARE CURSOR (Embedded SQL Directive).

OPEN (Executable Embedded SQL).

PREPARE (Executable Embedded SQL).

FETCH DESCRIPTOR (Executable Embedded SQL)

Purpose

To retrieve one or more rows returned by a query, assigning the select list values to host variables. Used in ANSI Dynamic SQL Method 4.

Prerequisites

You must first open the cursor with an the OPEN statement.

Syntax


Keywords and Parameters

FOR :array_size

FOR integer  

Host variable containing the number of rows to be processed.

Number of rows to be processed.

Limits the number of rows fetched if you are using array host variables. If you omit this clause, Oracle8i fetches enough rows to fill the smallest array.  

cursor  

A cursor that is declared by a DECLARE CURSOR statement. The FETCH statement returns one of the rows selected by the query associated with the cursor.  

cursor_variable  

A cursor variable is allocated an ALLOCATE statement. The FETCH statement returns one of the rows selected by the query associated with the cursor variable.  

INTO  

Specifies a list of host variables and optional indicator variables into which data is fetched. These host variables and indicator variables must be declared within the program.  

INTO 'descriptor name'

INTO :descriptor_name  

Name of the output ANSI descriptor.

Host variable containing the name of the output descriptor.  

GLOBAL | LOCAL  

LOCAL (the default) means file scope, as opposed to GLOBAL, which means application scope.  

Usage Notes

The number of rows retrieved is specified by the size of the output host variables and the value specified in the FOR clause. The host variables to receive the data must be either all scalars or all arrays. If they are scalars, Oracle8i fetches only one row. If they are arrays, Oracle8i fetches enough rows to fill the arrays.

Array host variables can have different sizes. In this case, the number of rows Oracle8i fetches is determined by the smaller of the following values:

Of course, the number of rows fetched can be further limited by the number of rows that actually satisfy the query.

If a FETCH statement does not retrieve all rows returned by the query, the cursor is positioned on the next returned row. When the last row returned by the query has been retrieved, the next FETCH statement results in an error code returned in the SQLCODE element of the SQLCA.

Note that the FETCH statement does not contain an AT clause. You must specify the database accessed by the cursor in the DECLARE CURSOR statement.

You can only move forward through the active set with FETCH statements. If you want to revisit any of the previously fetched rows, you must reopen the cursor and fetch each row in turn. If you want to change the active set, you must assign new values to the input host variables in the cursor's query and reopen the cursor.

Use DYNAMIC=ANSI precompiler option for the ANSI SQL Method 4 application. For more information, see "FETCH" for the ANSI SQL Method 4 application.

Example

...
EXEC SQL ALLOCATE DESCRIPTOR 'output_descriptor' END-EXEC.
...
EXEC SQL PREPARE S FROM :dyn_statement END-EXEC.
EXEC SQL DECLARE mycursor CURSOR FOR S END-EXEC.
...
EXEC SQL FETCH mycursor INTO DESCRIPTOR 'output_descriptor' END-EXEC.
...

Related Topics

PREPARE statement.

FREE (Executable Embedded SQL Extension)

Purpose

To free memory used by a cursor.

Prerequisites

The memory has to have been already allocated.

Syntax


Keywords and Parameters

cursor  

A cursor that is declared by a DECLARE CURSOR statement. The FETCH statement returns one of the rows selected by the query associated with the cursor.  

cursor_variable  

A cursor variable is allocated an ALLOCATE statement. It is of type SQL-CURSOR, or of type SQL-ROWID for a ROWID, or SQL-BLOB, SQL-CLOB, or SQL-NCLOB for a LOB.

The FETCH statement returns one of the rows selected by the query associated with the cursor variable.  

Usage Notes

See "Cursors" and "Cursor Variables".

Example

* CURSOR VARIABLE EXAMPLE
...
 01  CUR      SQL-CURSOR.
...
     EXEC SQL ALLOCATE :CUR END-EXEC.
...
     EXEC SQL CLOSE :CUR END-EXEC.
     EXEC SQL FREE  :CUR END-EXEC.
...

Related Topics

ALLOCATE (Executable Embedded SQL Extension).

CLOSE (Executable Embedded SQL).

DECLARE CURSOR (Embedded SQL Directive).

GET DESCRIPTOR (Executable Embedded SQL)

Purpose

To obtain information about host variables from a SQL descriptor area.

Prerequisites

Use only with value semantics and ANSI dynamic SQL Method 4.

Syntax


where item_name can be one of these choices:


Keywords and Parameters

array_size

integer  

Host variable containing the number of rows to be processed.

Number of rows to be processed.  

:descriptor_name  

Host variable containing the name of the allocated ANSI descriptor.  

'descriptor name'  

Name of the allocated ANSI descriptor.  

GLOBAL | LOCAL  

LOCAL (the default) means file scope, as opposed to GLOBAL, which means application scope.  

host_var=COUNT  

Host variable containing the total number of input or output variables.  

integer  

Total number of input or output variables.  

VALUE :host_integer  

Host variable containing the position of the referenced input or output variable.  

VALUE integer  

The position of the referenced input or output variable.  

host_var  

Host variable which will receive the item's value.  

item_name  

The item_name is found in Table 10-4, and Table 10-5, under the "Descriptor Item Name" column heading.  

Usage Notes

Use DYNAMIC=ANSI precompiler option. The array size clause can be used with DATA, RETURNED_LENGTH, and INDICATOR item names. See "GET DESCRIPTOR".

Example

     EXEC SQL GET DESCRIPTOR GLOBAL 'mydesc' :mydesc_num_vars = COUNT END-EXEC.

Related Topics

ALLOCATE DESCRIPTOR (Executable Embedded SQL).

DESCRIBE DESCRIPTOR (Executable Embedded SQL).

SET DESCRIPTOR (Executable Embedded SQL).

INSERT (Executable Embedded SQL)

Purpose

To add rows to a table or to a view's base table.

Prerequisites

For you to insert rows into a table, the table must be in your own schema or you must have INSERT privilege on the table.

For you to insert rows into the base table of a view, the owner of the schema containing the view must have INSERT privilege on the base table. Also, if the view is in a schema other than your own, you must have INSERT privilege on the view.

The INSERT ANY TABLE system privilege also allows you to insert rows into any table or any view's base table.

Syntax


where DML returning clause is:


Keywords and Parameters

AT  

Identifies the database on which the INSERT statement is executed. The database can be identified by either:  

 

db_name  

A database identifier declared in a previous DECLARE DATABASE statement.  

 

host_variable  

A host variable whose value is a previously declared db_name  

 

If you omit this clause, the INSERT statement is executed on your default database.  

FOR :host_integer  

Limits the number of times the statement is executed if the VALUES clause contains array host variables. If you omit this clause, Oracle8i executes the statement once for each component in the smallest array.  

schema  

The schema containing the table or view. If you omit schema, Oracle8i assumes the table or view is in your own schema.  

table

view  

The name of the table into which rows are to be inserted. If you specify view, Oracle8i inserts rows into the view's base table.  

db_link  

A complete or partial name of a database link to a remote database where the table or view is located. For information on referring to database links, see the Oracle8i SQL Reference. You can only insert rows into a remote table or view if you are using Oracle8i with the distributed option.

If you omit db_link, Oracle8i assumes that the table or view is on the local database.  

part_name  

The name of partition in the table  

column  

A column of the table or view. In the inserted row, each column in this list is assigned a value from the VALUES clause or the query.

If you omit one of the table's columns from this list, the column's value for the inserted row is the column's default value as specified when the table was created. If you omit the column list altogether, the VALUES clause or query must specify values for all columns in the table.  

VALUES  

Specifies a row of values to be inserted into the table or view. See the syntax description of expr in the Oracle8i SQL Reference. Note that the expressions can be host variables with optional indicator variables. You must specify an expression in the VALUES clause for each column in the column list.  

subquery  

A subquery that returns rows that are inserted into the table. The select list of this subquery must have the same number of columns as the column list of the INSERT statement. For the syntax description of a subquery, see "SELECT" in the Oracle8i SQL Reference.  

DML returning clause  

See "DML Returning Clause" for a discussion.  

Usage Notes

Any host variables that appear in the WHERE clause must be either all scalars or all arrays. If they are scalars, Oracle8 executes the INSERT statement once. If they are arrays, Oracle8i executes the INSERT statement once for each set of array components, inserting one row each time.

Array host variables in the WHERE clause can have different sizes. In this case, the number of times Oracle8i executes the statement is determined by the smaller of the following values:

For more information on this statement, see "The Basic SQL Statements".

Example I

This example illustrates the use of the embedded SQL INSERT statement:

     EXEC SQL 
         INSERT INTO EMP (ENAME, EMPNO, SAL) 
         VALUES (:ENAME, :EMPNO, :SAL)
     END-EXEC. 

Example II

This example shows an embedded SQL INSERT statement with a subquery:

     EXEC SQL 
         INSERT INTO NEWEMP (ENAME, EMPNO, SAL) 
         SELECT ENAME, EMPNO, SAL FROM EMP
         WHERE DEPTNO = :DEPTNO
     END-EXEC. 

Related Topics

DECLARE DATABASE (Oracle Embedded SQL Directive).

LOB APPEND (Executable Embedded SQL Extension)

Purpose

To append a LOB to the end of another LOB.

Prerequisites

LOB buffering must not be enabled.The destination LOB must have been initialized.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "APPEND".

Related Topics

See the other LOB statements.

LOB ASSIGN (Executable Embedded SQL Extension)

Purpose

To assign a LOB or BFILE locator to another locator.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "ASSIGN".

Related Topics

See the other LOB statements.

LOB CLOSE (Executable Embedded SQL Extension)

Purpose

To close an open LOB or BFILE.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "CLOSE" .

Related Topics

See the other LOB statements.

LOB COPY (Executable Embedded SQL Extension)

Purpose

To copy all or part of a LOB value into another LOB.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "COPY".

Related Topics

See the other LOB statements.

LOB CREATE TEMPORARY (Executable Embedded SQL Extension)

Purpose

To create a temporary LOB.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "CREATE TEMPORARY".

Related Topics

See the other LOB statements.

LOB DESCRIBE (Executable Embedded SQL Extension)

Purpose

To retrieve attributes from a LOB.

Syntax


where attrib is:


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "DESCRIBE".

Related Topics

See the other LOB statements.

LOB DISABLE BUFFERING (Executable Embedded SQL Extension)

Purpose

To disable LOB buffering.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "DISABLE BUFFERING".

Related Topics

See the other LOB statements.

LOB ENABLE BUFFERING (Executable Embedded SQL Extension)

Purpose

To enable LOB buffering.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see ENABLE BUFFERING

Related Topics

See the other LOB statements.

LOB ERASE (Executable Embedded SQL Extension)

Purpose

To erase a given amount of LOB data starting from a given offset.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "ERASE".

Related Topics

See the other LOB statements.

LOB FILE CLOSE ALL (Executable Embedded SQL Extension)

Purpose

To close all open BFILEs in the current session.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "FILE CLOSE ALL".

Related Topics

See the other LOB statements.

LOB FILE SET (Executable Embedded SQL Extension)

Purpose

To set DIRECTORY and FILENAME in a BFILE locator.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "FILE SET".

Related Topics

See the other LOB statements.

LOB FLUSH BUFFER (Executable Embedded SQL Extension)

Purpose

To write the LOB buffers to the database server.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "FLUSH BUFFER".

Related Topics

See the other LOB statements.

LOB FREE TEMPORARY (Executable Embedded SQL Extension)

Purpose

To free temporary space for the LOB locator.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "FREE TEMPORARY".

Related Topics

See the other LOB statements.

LOB LOAD (Executable Embedded SQL Extension)

Purpose

To copy all or part of a BFILE into an internal LOB.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "LOAD FROM FILE".

Related Topics

See the other LOB statements.

LOB OPEN (Executable Embedded SQL Extension)

Purpose

To open a LOB or BFILE for read or read/write access.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "OPEN".

Related Topics

See the other LOB statements.

LOB READ (Executable Embedded SQL Extension)

Purpose

To read all or part of a LOB or BFILE into a buffer.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "READ".

Related Topics

See the other LOB statements.

LOB TRIM (Executable Embedded SQL Extension)

Purpose

To truncate a LOB value.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "TRIM".

Related Topics

See the other LOB statements.

LOB WRITE (Executable Embedded SQL Extension)

Purpose

To write the contents of a buffer to a LOB.

Syntax


Usage Notes

For usage notes as well as keywords, parameters, and examples, see "WRITE".

Related Topics

See the other LOB statements.

OPEN (Executable Embedded SQL)

Purpose

To open a cursor, evaluating the associated query and substituting the host variable names supplied by the USING clause into the WHERE clause of the query. For the ANSI Dynamic SQL syntax, see "OPEN DESCRIPTOR (Executable Embedded SQL)".

Prerequisites

You must declare the cursor with a DECLARE CURSOR embedded SQL statement before opening it.

Syntax


Keywords and Parameters

array_size

integer  

Host variable containing the number of rows to be processed.

Number of rows to be processed.  

cursor  

The (previously declared) cursor to be opened.  

host_variable  

Specifies a host variable with an optional indicator variable to be substituted into the statement associated with the cursor.

CANNOT be used together with an ANSI descriptor (INTO clause).  

DESCRIPTOR SQLDA_descriptor  

Specifies an Oracle descriptor that describes the host variables to be substituted into the WHERE clause of the associated query. The descriptor must be initialized in a previous DESCRIBE statement. The substitution is based on position. The host variable names specified in this statement can be different from the variable names in the associated query.

CANNOT be used together with an ANSI descriptor (INTO clause).  

Usage Notes

The OPEN statement defines the active set of rows and initializes the cursor just before the first row of the active set. The values of the host variables at the time of the OPEN are substituted in the statement. This statement does not actually retrieve rows; rows are retrieved by the FETCH statement.

Once you have opened a cursor, its input host variables are not reexamined until you reopen the cursor. To change any input host variables and therefore the active set, you must reopen the cursor.

All cursors in a program are in a closed state when the program is initiated or when they have been explicitly closed using the CLOSE statement.

You can reopen a cursor without first closing it. For more information on this statement, see "Opening a Cursor".

Example

This example illustrates the use of the OPEN statement in a Pro*COBOL program:

     EXEC SQL DECLARE EMPCURSOR CURSOR FOR 
         SELECT ENAME, EMPNO, JOB, SAL 
         FROM EMP 
         WHERE DEPTNO = :DEPTNO
     END-EXEC. 
     EXEC SQL OPEN EMPCURSOR END-EXEC. 

Related Topics

CLOSE (Executable Embedded SQL) .

DECLARE CURSOR (Embedded SQL Directive) .

FETCH (Executable Embedded SQL).

PREPARE (Executable Embedded SQL) .

OPEN DESCRIPTOR (Executable Embedded SQL)

Purpose

To open a cursor (for ANSI Dynamic SQL Method 4), evaluating the associated query and substituting the input host variable names supplied by the USING clause into the WHERE clause of the query. The INTO clause denotes the output descriptor.

Prerequisites

You must declare the cursor with a DECLARE CURSOR embedded SQL statement before opening it.

Syntax

Keywords and Parameters

array_size

integer  

Host variable containing the number of rows to be processed.

Number of rows to be processed.  

cursor  

The (previously declared) cursor to be opened.  

USING DESCRIPTOR

descriptor_name 'descriptor name'  

Specifies an ANSI input descriptor with the host variable containing the name of the ANSI descriptor, or the name of the ANSI descriptor.  

INTO DESCRIPTOR descriptor_name 'descriptor name'  

Specifies an ANSI output descriptor with the host variable containing the name of the ANSI descriptor, or the name of the ANSI descriptor.  

GLOBAL | LOCAL  

LOCAL (the default) means file scope, as opposed to GLOBAL, which means application scope.  

Usage Notes

Set the precompiler option DYNAMIC to ANSI.

The OPEN statement defines the active set of rows and initializes the cursor just before the first row of the active set. The values of the host variables at the time of the OPEN are substituted in the statement. This statement does not actually retrieve rows; rows are retrieved by the FETCH statement.

Once you have opened a cursor, its input host variables are not reexamined until you reopen the cursor. To change any input host variables and therefore the active set, you must reopen the cursor.

All cursors in a program are in a closed state when the program is initiated or when they have been explicitly closed using the CLOSE statement.

You can reopen a cursor without first closing it. For more information on this statement, see "Inserting Rows".

Example

 01 DYN-STATEMENT PIC X(58) VALUE "SELECT ENAME, EMPNO FROM EMP WHERE
       DEPTNO =:DEPTNO-DAT".
 01 DEPTNO-DAT PIC S9(9) COMP VALUE 10.
 ...
     EXEC SQL ALLOCATE DESCRIPTOR 'input-descriptor' END-EXEC.
     EXEC SQL ALLOCATE DESCRIPTOR 'output-descriptor'
     ...
     EXEC SQL PREPARE S FROM :DYN-STATEMENT END-EXEC.
     EXEC SQL DECLARE C CURSOR FOR S END-EXEC.
     ...
     EXEC SQL OPEN C USING DESCRIPTOR 'input-descriptor' END-EXEC.
     ...

Related Topics

CLOSE (Executable Embedded SQL).

DECLARE CURSOR (Embedded SQL Directive).

FETCH DESCRIPTOR (Executable Embedded SQL) .

PREPARE (Executable Embedded SQL).

PREPARE (Executable Embedded SQL)

Purpose

To parse a SQL statement or PL/SQL block specified by a host variable and associate it with an identifier.

Prerequisites

None.

Syntax


Keywords and Parameters

db_name  

A null-terminated string containing the database connection name, as established previously in a CONNECT statement. If it is omitted, or if it is an empty string, the default database connection is assumed.  

host_variable  

A host variable containing the name of the database connection.  

array_size

integer  

Host variable containing the number of rows to be processed.

Number of rows to be processed.  

statement_id  

The identifier to be associated with the prepared SQL statement or PL/SQL block. If this identifier was previously assigned to another statement or block, the prior assignment is superseded.  

host_string  

A host variable whose value is the text of a SQL statement or PL/SQL block to be prepared.  

text  

A text literal containing the SQL statement or PL/SQL block to be executed. The quotes may be omitted.  

select_command  

A SELECT statement.  

Usage Notes

Any variables that appear in the host_string or text are placeholders. The actual host variable names are assigned in the USING clause of the OPEN statement (input host variables) or in the INTO clause of the FETCH statement (output host variables).

A SQL statement is prepared only once, but can be executed any number of times.

Example

This example illustrates the use of a PREPARE statement in a Pro*COBOL embedded SQL program:

     EXEC SQL PREPARE MYSTATEMENT FROM :MY-STRING END-EXEC. 
     EXEC SQL EXECUTE MYSTATEMENT END-EXEC.

Related Topics

CLOSE (Executable Embedded SQL).

DECLARE CURSOR (Embedded SQL Directive).

FETCH (Executable Embedded SQL).

OPEN (Executable Embedded SQL).

ROLLBACK (Executable Embedded SQL)

Purpose

To undo work done in the current transaction. You can also use this statement to manually undo the work done by an in-doubt distributed transaction.

Prerequisites

To roll back your current transaction, no privileges are necessary.

To manually roll back an in-doubt distributed transaction that you originally committed, you must have FORCE TRANSACTION system privilege. To manually roll back an in-doubt distributed transaction originally committed by another user, you must have FORCE ANY TRANSACTION system privilege.

Syntax


Keywords and Parameters

db_name  

A null-terminated string containing the database connection name, as established previously in a CONNECT statement. If it is omitted, or if it is an empty string, the default database connection is assumed.  

host_variable  

A host variable containing the name of the database connection.  

WORK  

Is optional and is provided for ANSI compatibility.  

TO  

Rolls back the current transaction to the specified savepoint. If you omit this clause, the ROLLBACK statement rolls back the entire transaction.  

FORCE  

Manually rolls back an in-doubt distributed transaction. The transaction is identified by the text containing its local or global transaction ID. To find the IDs of such transactions, query the data dictionary view DBA_2PC_PENDING.

ROLLBACK statements with the FORCE clause are not supported in PL/SQL.  

RELEASE  

Frees all resources and disconnects the application from the database server. The RELEASE clause is not allowed with SAVEPOINT and FORCE clauses.  

savepoint  

The name of the savepoint to be rolled back to.  

Usage Notes

A transaction (or a logical unit of work) is a sequence of SQL statements that Oracle8i treats as a single unit. A transaction begins with the first executable SQL statement after a COMMIT, ROLLBACK or connection to the database. A transaction ends with a COMMIT statement, a ROLLBACK statement, or disconnection (intentional or unintentional) from the database. Note that Oracle8i issues an implicit COMMIT statement before and after processing any Data Definition Language statement.

Using the ROLLBACK statement without the TO SAVEPOINT clause performs the following operations:

Using the ROLLBACK statement with the TO SAVEPOINT clause performs the following operations:

It is recommended that you explicitly end transactions in application programs using either a COMMIT or ROLLBACK statement. If you do not explicitly commit the transaction and the program terminates abnormally, Oracle8i rolls back the last uncommitted transaction.

Example I

The following statement rolls back your entire current transaction:

     EXEC SQL ROLLBACK END-EXEC. 

Example II

The following statement rolls back your current transaction to savepoint SP5:

      EXEC SQL ROLLBACK TO SAVEPOINT SP5 END-EXEC.

Distributed Transactions

Oracle8i with the distributed option allows you to perform distributed transactions, or transactions that modify data on multiple databases. To commit or roll back a distributed transaction, you need only issue a COMMIT or ROLLBACK statement as you would any other transaction.

If there is a network failure during the commit process for a distributed transaction, the state of the transaction may be unknown, or in-doubt. After consultation with the administrators of the other databases involved in the transaction, you may decide to manually commit or roll back the transaction on your local database. You can manually roll back the transaction on your local database by issuing a ROLLBACK statement with the FORCE clause.

For more information on when to roll back in-doubt transactions, see Oracle8i Distributed Database Systems.

You cannot manually roll back an in-doubt transaction to a savepoint.

A ROLLBACK statement with a FORCE clause only rolls back the specified transaction. Such a statement does not affect your current transaction.

Example III

The following statement manually rolls back an in-doubt distributed transaction:

     EXEC SQL ROLLBACK WORK FORCE '25.32.87' END-EXEC.

Related Topics

COMMIT (Executable Embedded SQL).

SAVEPOINT (Executable Embedded SQL).

SAVEPOINT (Executable Embedded SQL)

Purpose

To identify a point in a transaction to which you can later roll back.

Prerequisites

None.

Syntax


Keywords and Parameters

AT  

Identifies the database on which the savepoint is created. The database can be identified by either:  

 

db_name  

A database identifier declared in a previous DECLARE DATABASE statement.  

 

host_variable  

A host variable whose value is a previously declared db_name.  

 

If you omit this clause, the savepoint is created on your default database.  

savepoint  

The name of the savepoint to be created.  

Usage Notes

For more information on this statement, see "Using the SAVEPOINT Statement".

Example

This example illustrates the use of the embedded SQL SAVEPOINT statement:

     EXEC SQL SAVEPOINT SAVE3 END-EXEC.

Related Topics

COMMIT (Executable Embedded SQL).

ROLLBACK (Executable Embedded SQL).

SELECT (Executable Embedded SQL)

Purpose

To retrieve data from one or more tables, views, or snapshots, assigning the selected values to host variables.

Prerequisites

For you to select data from a table or snapshot, the table or snapshot must be in your own schema or you must have SELECT privilege on the table or snapshot.

For you to select rows from the base tables of a view, the owner of the schema containing the view must have SELECT privilege on the base tables. Also, if the view is in a schema other than your own, you must have SELECT privilege on the view.

The SELECT ANY TABLE system privilege also allows you to select data from any table or any snapshot or any view's base table.

Syntax



Keywords and Parameters

AT  

Identifies the database to which the SELECT statement is issued. The database can be identified by either:  

 

db_name  

A database identifier declared in a previous DECLARE DATABASE statement.  

 

host_variable  

A host variable whose value is a previously declared db_name.  

 

If you omit this clause, the SELECT statement is issued to your default database.  

select_list  

Identical to the non-embedded SELECT statement except that a host variables can be used in place of literals.  

INTO  

Specifies output host variables and optional indicator variables to receive the data returned by the SELECT statement. Note that these variables must be either all scalars or all arrays, but arrays need not have the same size.  

WHERE  

Restricts the rows returned to those for which the condition is TRUE. See the syntax description of condition in the Oracle8i SQL Reference. The condition can contain host variables, but cannot contain indicator variables. These host variables can be either scalars or arrays.  

All other keywords and parameters are identical to the non-embedded SQL SELECT statement.

Usage Notes

If no rows meet the WHERE clause condition, no rows are retrieved and Oracle8i returns an error code through the SQLCODE component of the SQLCA.

You can use comments in a SELECT statement to pass instructions, or hints, to the Oracle8i optimizer. The optimizer uses hints to choose an execution plan for the statement. For more information on hints, see Oracle8i Tuning.

Example

This example illustrates the use of the embedded SQL SELECT statement:

     EXEC SQL SELECT ENAME, SAL + 100, JOB 
         INTO :ENAME, :SAL, :JOB 
         FROM EMP 
         WHERE EMPNO = :EMPNO
     END-EXEC. 

Related Topics

DECLARE CURSOR (Embedded SQL Directive).

DECLARE DATABASE (Oracle Embedded SQL Directive).

EXECUTE (Executable Embedded SQL).

FETCH (Executable Embedded SQL).

PREPARE (Executable Embedded SQL).

SET DESCRIPTOR (Executable Embedded SQL)

Purpose

Use this ANSI dynamic SQL statement to set information in the descriptor area from host variables.

Prerequisites

Use after a DESCRIBE DESCRIPTOR.

Syntax


where item_name can be one of these choices:

Keywords and Parameters

:

array_size

integer  

Host variable containing the number of rows to be processed.

Number of rows to be processed. The array size clause can only be used with DATA, RETURNED_LENGTH and INDICATOR item names.  

GLOBAL | LOCAL  

LOCAL (the default) means file scope, as opposed to GLOBAL, which means application scope.  

descriptor_name

'descriptor name'  

Host variable containing the name of the allocated ANSI descriptor.

Name of the allocated ANSI descriptor.  

COUNT  

The total number of input or output variables.  

VALUE  

The position of the referenced host variable in the statement.  

item_name  

See Table 10-6, and Table 10-7 for lists of the item_names, and their descriptions.  

host_var  

Host variable containing the total number of input or output variables.  

integer  

Total number of input or output variables.  

host_var  

The host variables used to set the item.  

REF  

Reference semantics are to be used. Can be used only with RETURNED_LENGTH, DATA, and INDICATOR item names.

Must be used to set RETURNED_LENGTH.  

Usage Notes

Use DYNAMIC=ANSI precompiler option. Set CHARACTER_SET_NAME to UTF16 for client-side Unicode support. See "SET DESCRIPTOR" for complete details, including tables of descriptor item names.

Example

     EXEC SQL SET DESCRIPTOR GLOBAL :mydescr COUNT = 3 END-EXEC.

Related Topics

ALLOCATE DESCRIPTOR (Executable Embedded SQL).

DEALLOCATE DESCRIPTOR (Embedded SQL Statement).

DESCRIBE DESCRIPTOR (Executable Embedded SQL).

GET DESCRIPTOR (Executable Embedded SQL).

PREPARE (Executable Embedded SQL).

UPDATE (Executable Embedded SQL)

Purpose

To change existing values in a table or in a view's base table.

Prerequisites

For you to update values in a table or snapshot, the table must be in your own schema or you must have UPDATE privilege on the table.

For you to update values in the base table of a view, the owner of the schema containing the view must have UPDATE privilege on the base table. Also, if the view is in a schema other than your own, you must have UPDATE privilege on the view.

The UPDATE ANY TABLE system privilege also allows you to update values in any table or any view's base table.

Syntax


where DML returning clause is:


Keywords and Parameters

AT  

identifies the database to which the UPDATE statement is issued. The database can be identified by either:  

 

dbname  

A database identifier declared in a previous DECLARE DATABASE statement.  

 

host_variable  

A host variable whose value is a previously declared dbname.  

 

If you omit this clause, the UPDATE statement is issued to your default database.  

FOR :host_integer  

Limits the number of times the UPDATE statement is executed if the SET and WHERE clauses contain array host variables. If you omit this clause, Oracle8i executes the statement once for each component of the smallest array.  

schema  

The schema containing the table or view. If you omit schema, Oracle8i assumes the table or view is in your own schema.  

table view  

The name of the table to be updated. If you specify view, Oracle8i updates the view's base table.  

dblink  

A complete or partial name of a database link to a remote database where the table or view is located. For information on referring to database links, see the Oracle8i SQL Reference. You can only use a database link to update a remote table or view if you are using Oracle8i with the distributed option.  

part_name  

Name of partition in the table  

alias  

A name used to reference the table, view, or subquery elsewhere in the statement.  

column  

The name of a column of the table or view that is to be updated. If you omit a column of the table from the SET clause, that column's value remains unchanged.  

expr  

The new value assigned to the corresponding column. This expression can contain host variables and optional indicator variables. See the syntax of expr in the Oracle8i SQL Reference.  

subquery_1  

A subquery that returns new values that are assigned to the corresponding columns. For the syntax of a subquery, see "SELECT" in the Oracle8i SQL Reference.  

subquery_2  

A subquery that return a new value that is assigned to the corresponding column. For the syntax of a subquery, see "SELECT" in the Oracle8i SQL Reference.  

WHERE  

Specifies which rows of the table or view are updated:  

 

condition  

Updates only rows for which this condition is true. This condition can contain host variables and optional indicator variables. See the syntax of condition in the Oracle8i SQL Reference.  

 

CURRENT OF  

Updates only the row most recently fetched by the cursor. The cursor cannot be associated with a SELECT statement that performs a join unless its FOR UPDATE clause explicitly locks only one table.  

 

If you omit this clause entirely, Oracle8i updates all rows of the table or view.  

DML returning clause  

See "DML Returning Clause" for a discussion.  

Usage Notes

Host variables in the SET and WHERE clauses must be either all scalars or all arrays. If they are scalars, Oracle8i executes the UPDATE statement only once. If they are arrays, Oracle8i executes the statement once for each set of array components. Each execution may update zero, one, or multiple rows.

Array host variables can have different sizes. In this case, the number of times Oracle8i executes the statement is determined by the smaller

of the following values:

The cumulative number of rows updated is returned through the third element of the SQLERRD component of the SQLCA. When arrays are used as input host variables, this count reflects the total number of updates for all components of the array processed in the UPDATE statement. If no rows satisfy the condition, no rows are updated and Oracle8i returns an error message through the SQLCODE element of

the SQLCA. If you omit the WHERE clause, all rows are updated and Oracle8i raises a warning flag in the fifth component of the SQLWARN element of the SQLCA.

You can use comments in an UPDATE statement to pass instructions, or hints, to the Oracle8i optimizer. The optimizer uses hints to choose an execution plan for the statement. For more information on hints, see Oracle8i Tuning.

For more information on this statement, see "The Basic SQL Statements" andChapter 3, "Database Concepts".

Examples

The following examples illustrate the use of the embedded SQL UPDATE statement:

     EXEC SQL UPDATE EMP 
         SET SAL = :SAL, COMM = :COMM INDICATOR :COMM-IND 
         WHERE ENAME = :ENAME
     END-EXEC. 
 
     EXEC SQL UPDATE EMP 
         SET (SAL, COMM) = 
             (SELECT AVG(SAL)*1.1, AVG(COMM)*1.1 
             FROM EMP) 
         WHERE ENAME = 'JONES'
     END-EXEC. 

Related Topics

DECLARE DATABASE (Oracle Embedded SQL Directive).

VAR (Oracle Embedded SQL Directive)

Purpose

To perform host variable equivalencing, or to assign a specific Oracle8i external datatype to an individual host variable, overriding the default datatype assignment. There is an optional clause, CONVBUFSZ , that specifies the size of a buffer for character set conversion.

Prerequisites

The host variable must be previously declared in the embedded SQL program.

Syntax


Keywords and Parameters

host_variable  

The host variable to be assigned an Oracle8i external datatype.  

dtyp  

An Oracle8i external datatype recognized by Pro*COBOL (not an Oracle8i internal datatype). The datatype may include a length, precision, or scale. This external datatype is assigned to the host_variable. For a list of external datatypes, see "External Datatypes".  

size  

The size in bytes of a buffer in the Oracle8i runtime library used to perform conversion between character sets of the host_variable.  

Usage Notes

Host variable equivalencing is one kind of datatype equivalencing. Datatype equivalencing is useful for any of the following purposes:

For more information about Oracle datatypes, see "Sample Program 4: Datatype Equivalencing".

Example

This example equivalences the host variable DEPT_NAME to the datatype STRING and the host variable BUFFER to the datatype RAW(200):

     EXEC SQL BEGIN DECLARE SECTION END-EXEC. 
     ... 
     01 DEPT-NAME  PIC X(15).
* -- default datatype is CHAR 
     EXEC SQL VAR DEPT-NAME IS STRING END-EXEC.
* -- reset to STRING 
     ...
     01 BUFFER-VAR.
          05 BUFFER  PIC X(200).     
* -- default datatype is CHAR 
     EXEC SQL VAR BUFFER IS RAW(200) END-EXEC.
* -- refer to RAW 
     ...
     EXEC SQL END DECLARE SECTION END-EXEC. 

Related Topics

None.

WHENEVER (Embedded SQL Directive)

Purpose

To specify the action to be taken when an error or warning results from executing an embedded SQL program.

Prerequisites

None.

Syntax


where DO.CALL.CLAUSE is:


Keywords and Parameters

NOT FOUND | NOTFOUND  

Identifies any exception condition that returns an error code of +1403 to SQLCODE (or a +100 code when MODE=ANSI).  

SQLERROR  

Identifies a condition that results in a negative return code.  

SQLWARNING  

Identifies a non-fatal warning condition.  

CONTINUE  

Indicates that the program should progress to the next statement.  

GOTO | GO TO  

Indicates that the program should branch to the statement named by label.  

STOP  

Stops program execution.  

DO PERFORM  

Indicates that the program should perform a paragraph at label.  

DO CALL  

Indicates that the program should execute a subprogram.  

subprogram_name  

The subprogram to be executed. It may have to be inside quotes (").  

USING  

Indicates that the parameters of the subprogram follow.  

param  

A list of subprogram parameters separated by blanks.  

The WHENEVER directive allows your program to teke one of several possible actions in the event an embedded SQL statement results in an error or warning.

The scope of a WHENEVER statement is positional, rather than logical. A WHENEVER statement applies to all embedded SQL statements that textually follow it in the source file, not in the flow of the program logic. A WHENEVER statement remains in effect until it is superseded by another WHENEVER statement checking for the same condition.

For more information about and examples of the conditions and actions of this directive, see "WHENEVER Directive".

Do not confuse the WHENEVER embedded SQL directive with the WHENEVER SQL*Plus command.

Example

The following example illustrates the use of the WHENEVER directive in a Pro*COBOL embedded SQL program:

     EXEC SQL WHENEVER NOT FOUND CONTINUE END-EXEC.
     ... 
     EXEC SQL WHENEVER SQLERROR GOTO SQL-ERROR END-EXEC. 
     ... 
 SQL-ERROR. 
     EXEC SQL WHENEVER SQLERROR CONTINUE END-EXEC. 
     DISPLAY "ORACLE ERROR DETECTED.".
     EXEC SQL ROLLBACK RELEASE END-EXEC.
     STOP RUN. 

Related Topics

None




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