Re: Using DataStructure in Update Query in RPG ?

["Dave Odom" <Dave.Odom@xxxxxxxxxxxx>]

Luqman,

Let me give you a few examples in different languages and see if this
helps.   If not, please explain further.   The following are examples of
the UPDATE statement using  data structures in programs in C, COBOL and
REXX:

void main ()
{
EXEC SQL BEGIN DECLARE SECTION;
decimal(5,2) AMOUNT;
char FROM_EMPNO[7];
char TO_EMPNO[7];
EXEC SQL END DECLARE SECTION;
EXEC SQL INCLUDE SQLCA;
EXEC SQL WHENEVER SQLERROR GOTO SQLERR;
...
EXEC SQL UPDATE EMPLOYEE
SET COMM = COMM - :AMOUNT
WHERE EMPNO = :FROM_EMPNO;
EXEC SQL UPDATE EMPLOYEE
SET COMM = COMM + :AMOUNT
WHERE EMPNO = :TO_EMPNO;
FINISHED:
EXEC SQL COMMIT WORK;
return;

For example, in COBOL:
01 SAL-REC.
10 MIN-SAL PIC S9(6)V99 USAGE COMP-3.
10 AVG-SAL PIC S9(6)V99 USAGE COMP-3.
10 MAX-SAL PIC S9(6)V99 USAGE COMP-3.
01 SALTABLE.
02 SALIND PIC S9999 USAGE COMP-4 OCCURS 3 TIMES.
01 EDUC-LEVEL PIC S9999 COMP-4.
...
MOVE 20 TO EDUC-LEVEL.
...
EXEC SQL
SELECT MIN(SALARY), AVG(SALARY), MAX(SALARY)
INTO :SAL-REC:SALIND
FROM CORPDATA.EMPLOYEE
WHERE EDLEVEL>:EDUC-LEVEL
END-EXEC.

REXX:

ADDRESS '*COMMAND',
SIGNAL ON ERROR
UPDATE_STMT = 'UPDATE CORPDATA/EMPLOYEE ',     
       'SET SALARY = SALARY * ?  ',            
         'WHERE COMM >= ?          '           
         EXECSQL,                              
              'PREPARE S1 FROM :UPDATE_STMT'   
               EXECSQL,                        
              'EXECUTE S1 USING :PERCENTAGE,', 
         '                 :COMMISSION '       
           /* Commit changes */                
EXECSQL, 
    'COMMIT'

HTH,

Dave