SQL/MX Programming Manual for C and COBOL (G06.24+, H06.03+)

COBOL Sample Programs
HP NonStop SQL/MX Programming Manual for C and COBOL—523627-004
C-10
Using SQL Descriptor Areas in Dynamic SQL
PROCEDURE DIVISION.
START-LABEL.
DISPLAY "This example uses SQL descriptor areas".
EXEC SQL WHENEVER SQLERROR GOTO sqlerrors END-EXEC.
* Initialize the output variable in SELECT list.
DISPLAY "Enter the columns to be retrieved,"
& " separated by commas: ".
ACCEPT in-columns.
DISPLAY hv-sql-stmt.
* Allocate SQL descriptor area for input parameters.
MOVE 1 TO hv-desc-max.
EXEC SQL
ALLOCATE DESCRIPTOR 'in_sqlda' WITH MAX :hv-desc-max
END-EXEC.
* Allocate SQL descriptor area for output values.
MOVE 6 TO hv-desc-max.
EXEC SQL
ALLOCATE DESCRIPTOR 'out_sqlda' WITH MAX :hv-desc-max
END-EXEC.
* Prepare dynamic SQL statement.
MOVE hv-sql-stmt TO hv-prepare-stmt.
EXEC SQL
PREPARE sqlstmt FROM :hv-prepare-stmt
END-EXEC.
* Describe the SQL descriptor area for input parameters.
EXEC SQL
DESCRIBE INPUT sqlstmt USING SQL DESCRIPTOR 'in_sqlda'
END-EXEC.
* Describe the SQL descriptor area for SELECT values.
EXEC SQL
DESCRIBE OUTPUT sqlstmt USING SQL DESCRIPTOR 'out_sqlda'
END-EXEC.
* Initialize the input parameter in the WHERE clause
DISPLAY "Enter the employee number to be retrieved: ".
ACCEPT in-empnum.
* Set the value of the input parameter in
* the input SQL descriptor area
MOVE 1 TO hv-desc-value.
EXEC SQL
SET DESCRIPTOR 'in_sqlda' VALUE :hv-desc-value
VARIABLE_DATA = :in-empnum
END-EXEC.
Example C-4. Using Descriptor Areas With DESCRIBE (page 2 of 4)