DB2 Application Programming

COBOL-DB2 interface is governed by following rules:-

• Embedded SQL statement must be enclosed between “EXEC SQL” and “END-EXEC”
• Example:-
  EXEC SQL        SELECT EMP-ID INTO :WS-ID FROM EMP END-EXEC.

• Each EXEC SQL ... END-EXEC block must contain only one SQL statement.
• If the SQL command is not terminated by an END-EXEC operand, a COBOL compiler error will be generated.
• All SQL statements must be coded in Margin B.
• All SQL statements except INCLUDE and DECLARE must be coded in PROCEDURE DIVISION
• Structure (or Definition) of all the DB2 tables used withing program should have been included in WORKING-STORAGE SECTION using EXEC SQL INCLUDE statement
• All the Host Variables used in program must be declared in WORKING-STORAGE SECTION.
• Always suggested to include SQLCA to track SQL return code of executed SQL Statement. SQLCA is explained in following section.