Using Database Operations

VSAM Adapter Database Operations (JCD)

The same database operations are also used in the JCD, but appear as methods to call from the Collaboration.

Tables and Views are manipulated through OTDs. Methods to call include:

insert()
insertRow()
update(String sWhere)
updateRow()
delete(String sWhere)
deleteRow()
select(String where)

Note –
Refer to the Javadoc for a full description of methods included in the VSAM Adapter.

The Table

A table OTD represents a database table. It consists of fields and methods. Fields correspond to the columns of a table while methods are the operations that you can apply to the OTD. This allows you to perform query, update, insert, and delete SQL operations in a table. The ability to update via a resultset is called “Updatable Resultset”, which is a feature supported by this adapter.

By default, the Table OTD has UpdatableConcurrency and ScrollTypeForwardOnly. Normally you do not have to change the default setting.

The type of result returned by the select() method can be specified using:

SetConcurrencytoUpdatable
SetConcurrencytoReadOnly
SetScrollTypetoForwardOnly
SetScrollTypetoScrollSensitive
SetScrollTypetoInsensitive

The Query (Select) Operation

To perform a query operation on a table:

Execute the select() method with the “where” clause specified if necessary.

Loop through the ResultSet using the next() method.

Process the return record within a while() loop.

For example:

package prjVSAM_JCDjcdALL;

public class jcdTableSelect
{

    public com.stc.codegen.logger.Logger logger;

    public com.stc.codegen.alerter.Alerter alerter;

    public com.stc.codegen.util.CollaborationContext collabContext;

    public com.stc.codegen.util.TypeConverter typeConverter;

    public void receive( com.stc.connector.appconn.file.
FileTextMessage input, otdVSAM.OtdVSAMOTD otdVSAM_1, dtd.
otdOutputDTD_1935483687.Emp otdOutputDTD_Emp_1, com.stc.connector.
appconn.file.FileApplication FileClient_1 )
        throws Throwable
    {
        FileClient_1.setText( "Selecting record(s) from CICSEMP
table via table select .." );
        FileClient_1.write();
        otdVSAM_1.getCICSEMP().select( input.getText() );
        while (otdVSAM_1.getCICSEMP().next()) {
            otdOutputDTD_Emp_1.setENAME( otdVSAM_1.getCICSEMP().getENAME() );
            otdOutputDTD_Emp_1.setPHONE( typeConverter.intToString( otdVSAM_1.
getCICSEMP().getPHONE(), "#", false, "" ) );
            otdOutputDTD_Emp_1.setMAILID( otdVSAM_1.getCICSEMP().getMAILID() );
            otdOutputDTD_Emp_1.setSALARY( otdVSAM_1.getCICSEMP().getSALARY().
toString() );
            otdOutputDTD_Emp_1.setJOBID( typeConverter.doubleToString(
 otdVSAM_1.getCICSEMP().getJOBID(), "#.000000;-#.000000", false, "" ) );
            otdOutputDTD_Emp_1.setEMPID( typeConverter.intToString(
 otdVSAM_1.getCICSEMP().getEMPID(), "#", false, "" ) );
            otdOutputDTD_Emp_1.setDEPTID( typeConverter.shortToString(
 otdVSAM_1.getCICSEMP().getDEPTID(), "#", false, "" ) );
            otdOutputDTD_Emp_1.setDEPARTMENT( otdVSAM_1.getCICSEMP().getDEPARTMENT() );
            FileClient_1.setText( otdOutputDTD_Emp_1.marshalToString() );
            FileClient_1.write();
        }
        FileClient_1.setText( "Done table select." );
        FileClient_1.write();
    }

}

The Insert Operation

To perform an insert operation on a table:

Execute the insert() method. Assign a field.

Insert the row by calling insertRow()

This example inserts an employee record:

package prjVSAM_JCDjcdALL;

public class jcdInsert
{

    public com.stc.codegen.logger.Logger logger;

    public com.stc.codegen.alerter.Alerter alerter;

    public com.stc.codegen.util.CollaborationContext collabContext;

    public com.stc.codegen.util.TypeConverter typeConverter;

    public void receive( com.stc.connector.appconn.file.FileTextMessage input,
 dtd.otdInputDTD_622919076.Emp otdInputDTD_Emp_1, otdVSAM.OtdVSAMOTD otdVSAM_1,
 com.stc.connector.appconn.file.FileApplication FileClient_1 )
        throws Throwable
    {
        FileClient_1.setText( "Inserting records into CICSEMP table .." );
        FileClient_1.write();
        otdInputDTD_Emp_1.unmarshalFromString( input.getText() );
        otdVSAM_1.getCICSEMP().insert();
        for (int i1 = 0; i1 < otdInputDTD_Emp_1.countX_sequence_A(); i1 += 1) {
            otdVSAM_1.getCICSEMP().setENAME(
 otdInputDTD_Emp_1.getX_sequence_A( i1 ).getENAME() );
            otdVSAM_1.getCICSEMP().setPHONE( typeConverter.stringToInt(
 otdInputDTD_Emp_1.getX_sequence_A( i1 ).getPHONE(), "#", false, 0 ) );
            otdVSAM_1.getCICSEMP().setMAILID( otdInputDTD_Emp_1.getX_sequence_A(
 i1 ).getMAILID() );
            otdVSAM_1.getCICSEMP().setSALARY( new java.math.BigDecimal(
 otdInputDTD_Emp_1.getX_sequence_A( i1 ).getSALARY() ) );
            otdVSAM_1.getCICSEMP().setJOBID( typeConverter.stringToDouble(
 otdInputDTD_Emp_1.getX_sequence_A( i1 ).getJOBID(), "#.000000;-#.000000",
 false, 0 ) ); otdVSAM_1.getCICSEMP().setEMPID( typeConverter.stringToInt(
 otdInputDTD_Emp_1.getX_sequence_A( i1 ).getEMPID(), "#", false, 0 ) );
            otdVSAM_1.getCICSEMP().setDEPTID( typeConverter.stringToShort(
 otdInputDTD_Emp_1.getX_sequence_A( i1 ).getDEPTID(), "#", false, 0 ) );
            otdVSAM_1.getCICSEMP().setDEPARTMENT( otdInputDTD_Emp_1.getX_sequence_A(
 i1 ).getDEPARTMENT() );
            otdVSAM_1.getCICSEMP().insertRow();
        }
        FileClient_1.setText( "Done Insert." );
        FileClient_1.write();
    }
}

The Update Operation

To perform an update operation on a table:

Execute the update() method.

Using a while loop together with next(), move to the row that you want to update.

Assign updating value(s) to the fields of the table OTD

Update the row by calling updateRow().

package prjVSAM_JCDjcdALL;

public class jcdUpdate
{

    public com.stc.codegen.logger.Logger logger;

    public com.stc.codegen.alerter.Alerter alerter;

    public com.stc.codegen.util.CollaborationContext collabContext;

    public com.stc.codegen.util.TypeConverter typeConverter;

    public void receive( com.stc.connector.appconn.file.FileTextMessage
input, otdVSAM.OtdVSAMOTD otdVSAM_1, dtd.otdOutputDTD_1935483687.
Emp otdOutputDTD_Emp_1, com.stc.connector.appconn.file.FileApplication FileClient_1 )
        throws Throwable
    {
        FileClient_1.setText( "Update the Department .. " );
        FileClient_1.write();
        otdVSAM_1.getCICSEMP().update( input.getText() );
        while (otdVSAM_1.getCICSEMP().next()) {
            otdVSAM_1.getCICSEMP().setDEPARTMENT( "QAQAQA" );
            otdVSAM_1.getCICSEMP().updateRow();
        }
        FileClient_1.setText( "Done Update." );
        FileClient_1.write();
    }

}

The Delete Operation

To perform a delete operation on a table:

Execute the delete() method.

In this example DELETE an employee.

package prjVSAM_JCDjcdALL;

public class jcdDelete
{

    public com.stc.codegen.logger.Logger logger;

    public com.stc.codegen.alerter.Alerter alerter;

    public com.stc.codegen.util.CollaborationContext collabContext;

    public com.stc.codegen.util.TypeConverter typeConverter;

    public void receive( com.stc.connector.appconn.file.
FileTextMessage input, otdVSAM.OtdVSAMOTD otdVSAM_1, dtd.
otdOutputDTD_1935483687.Emp otdOutputDTD_Emp_1, com.stc.connector.
appconn.file.FileApplication FileClient_1 )
        throws Throwable
    {
        FileClient_1.setText( "Delete record .." );
        FileClient_1.write();
        otdVSAM_1.getCICSEMP().delete( input.getText() );
        FileClient_1.setText( "Done delete." );
        FileClient_1.write();
    }

}

Prepared Statement

A Prepared Statement OTD represents a SQL statement that has been compiled. Fields in the OTD correspond to the input values that users need to provide.

Prepared statements can be used to perform insert, update, delete and query operations. A prepared statement uses a question mark (?) as a place holder for input. For example:

insert into EMP_TAB(Age, Name, Dept No) value(?, ?, ?)

To execute a prepared statement, set the input parameters and call executeUpdate() and specify the input values if any.

getPrepStatement().getPreparedStatementTest().setAge(23);
getPrepStatement().getPreparedStatementTest().setName(”Peter Pan’);
getPrepStatement().getPreparedStatementTest().setDeptNo(6);
getPrepStatement().getPreparedStatementTest().executeUpdate();

Batch Operations

To achieve better performance, consider using a bulk insert if you have to insert many records. This is the “Add Batch” capability. The only modification required is to include the addBatch() method for each SQL operation and then the executeBatch() call to submit the batch to the database server. Batch operations apply only to Prepared Statements.

getPrepStatement().getPreparedStatementTest().setAge(23);
getPrepStatement().getPreparedStatementTest().setName(”Peter Pan’);
getPrepStatement().getPreparedStatementTest().setDeptNo(6);
getPrepStatement().getPreparedStatementTest().addBatch();

getPrepStatement().getPreparedStatementTest().setAge(45);
getPrepStatement().getPreparedStatementTest().setName(”Harrison Ford’);
getPrepStatement().getPreparedStatementTest().setDeptNo(7);
getPrepStatement().getPreparedStatementTest().addBatch();
getPrepStatement().getPreparedStatementTest().executeBatch();