24.37 OPEN_REMOTE_DML_CONTEXT Function

This function opens a DML context based for a remote database.

Syntax

function open_remote_dml_context (
    p_server_static_id      IN VARCHAR2,
    --
    p_columns               IN t_columns               DEFAULT c_empty_columns,
    p_query_type            IN t_query_type,
    --     
    p_table_owner           IN VARCHAR2                DEFAULT NULL,
    p_table_name            IN VARCHAR2                DEFAULT NULL,
    p_where_clause          IN VARCHAR2                DEFAULT NULL,  
    --
    p_sql_query             IN VARCHAR2                DEFAULT NULL,
    p_plsql_function_body   IN VARCHAR2                DEFAULT NULL,
    --
    p_with_check_option     IN BOOLEAN                 DEFAULT TRUE,
    p_optimizer_hint        IN VARCHAR2                DEFAULT NULL,
    --
    p_dml_table_owner       IN VARCHAR2                DEFAULT NULL,
    p_dml_table_name        IN VARCHAR2                DEFAULT NULL,
    p_dml_plsql_code        IN VARCHAR2                DEFAULT NULL,
    --
    p_lost_update_detection IN t_lost_update_detection DEFAULT NULL,
    p_lock_rows             IN t_lock_rows             DEFAULT NULL,
    p_lock_plsql_code       IN VARCHAR2                DEFAULT NULL,
    --
    p_sql_parameters        IN t_parameters            DEFAULT c_empty_parameters )
    RETURN t_context;

Parameters

Table 24-32 OPEN_REMOTE_DML_CONTEXT Function Parameters

Parameter Description

p_server_static_id

Static ID of the ORDS REST Enabled SQL Instance.

p_columns

DML columns to pass to the Data Source.

p_query_type

DML columns to pass to the Data Source. Indicates the type of the Data Source.

Possible values are:
  • c_query_type_table: Use a plain Table as the data source.
  • c_query_type_sql_query: Use a SQL query as the data source.
  • c_query_type_func_return_sql: Use the SQL query returned by the PL/SQL function.

p_table_owner

For query type TABLE: Table owner.

p_table_name

For query type TABLE: Table name.

p_where_clause

For query type TABLE: where clause.

p_sql_query

For query type SQL QUERY: the query.

p_plsql_function_body

For query type PLSQL: the PL/SQL function which returns the SQL query.

p_with_check_option

Specify whether to the "WITH CHECK OPTION" should be added to the data source. If set to "TRUE" (default), INSERTED or UPDATED rows cannot violate the where clause.

p_optimizer_hint

Optimizer hints to be added to the DML clause.

p_dml_table_owner

When set, DML statements will be executed against this table.

p_dml_table_name

When set, DML statements will be executed against this table.

p_dml_plsql_code

Custom PL/SQL code to be executed instead of DML statements.

p_lost_update_detection

Lost-update detection type. Possible values are:
  • c_lost_update_implicit: APEX calculates a checksum from the row values
  • c_lost_update_explicit: One of the p_columns has the "is_checksum" attribute set
  • c_lost_update_none: No lost update detection

p_lock_rows

Specify whether to lock the rows for the (short) time frame between the lost update detection and the actual DML statement.

Possible values are:
  • c_lock_rows_automatic: use a SELECT .. FOR UPDATE
  • c_lock_rows_plsql: use custom PL/SQL code to lock the rows
  • c_lock_rows_none: do not lock rows

p_dml_plsql_code

Custom PL/SQL code to be used to lock the rows.

p_sql_parameters

Bind variables to be used.

Returns

The context object representing the DML handle.

Example

The following inserts one row into the EMP table on a REST Enabled SQL Service.

DECLARE
    l_columns        apex_exec.t_columns;
    l_context        apex_exec.t_context;
BEGIN
    -- I. Define DML columns
    apex_exec.add_column(
       p_columns        => l_columns,
       p_column_name    => 'EMPNO',
       p_data_type      => apex_exec.c_data_type_number,
       p_is_primary_key => true );
    apex_exec.add_column(
       p_columns        => l_columns,
       p_column_name    => 'ENAME',
       p_data_type      => apex_exec.c_data_type_varchar2 );
    apex_exec.add_column(
       p_columns        => l_columns,
       p_column_name    => 'JOB',
       p_data_type      => apex_exec.c_data_type_varchar2 );
    apex_exec.add_column(
       p_columns        => l_columns,
       p_column_name    => 'HIREDATE',
       p_data_type      => apex_exec.c_data_type_date );
    apex_exec.add_column(
       p_columns        => l_columns,
       p_column_name    => 'MGR',
       p_data_type      => apex_exec.c_data_type_number );
    apex_exec.add_column(
       p_columns        => l_columns,
       p_column_name    => 'SAL',
       p_data_type      => apex_exec.c_data_type_number );
    apex_exec.add_column(
       p_columns        => l_columns,
       p_column_name    => 'COMM',
       p_data_type      => apex_exec.c_data_type_number );
    apex_exec.add_column(
       p_columns        => l_columns,
       p_column_name    => 'DEPTNO',
       p_data_type      => apex_exec.c_data_type_number );
    
    -- II. Open the context object
    l_context := apex_exec.open_remote_dml_context(
       p_server_static_id      => '{remote server static id}',
       p_columns               => l_columns,
       p_query_type            => apex_exec.c_query_type_sql_query,
       p_sql_query             => 'select * from emp where deptno = 10',
       p_lost_update_detection => apex_exec.c_lost_update_none );
    
    -- III. Provide DML data
        
    apex_exec.add_dml_row(
       p_context   => l_context,
       p_operation => apex_exec.c_dml_operation_insert );
    
    apex_exec.set_value(
       p_context         => l_context,
       p_column_position => 1,
       p_value           => 4711 );
    apex_exec.set_value(
       p_context         => l_context,
       p_column_position => 2,
       p_value           => 'DOE' );
    apex_exec.set_value(
       p_context         => l_context,
       p_column_position => 3,
       p_value           => 'DEVELOPR' );
    apex_exec.set_value(
       p_context         => l_context,
       p_column_position => 4,
       p_value           => sysdate );
    apex_exec.set_value(
       p_column_position => 6,
       p_value           => 1000 );
    apex_exec.set_value(
       p_context         => l_context,
       p_column_position => 8,
       p_value           => 10 );
    
    -- IV: Execute the DML statement
        
    apex_exec.execute_dml(
       p_context           => l_context,
       p_continue_on_error => false);
       apex_exec.close( l_context );
EXCEPTION
    when others then
        apex_exec.close( l_context );
        raise;
END;