Arrays and structures as indicator variables

For tables with a large number of columns, you can use arrays and structures as a set of host variables that is referenced in a SQL statement. For this feature to work correctly, you must declare the indicator array or indicator structure elements with a PIC S9(4) clause and a COMP-5 clause. As with ESQL/C, use of structures and arrays as indicator variables removes the time consuming process of coding singleton indicator variables in ESQL/COBOL for every nullable column of every Embedded SQL statement in the application.

Example 1 This is an example of declaring indicator arrays and executing a query on the indicator arrays:

* Declare variables
....
01 HOST-STRUCTURE-M1.
   03 M-TITLE PIC X(64).
   03 M-NOTES PIC X(200).
   03 M-PUBNAME PIC X(40).
   03 M-PUBCITY PIC X(20).
   03 M-PUBSTATE PIC X(2).

01 INDICATOR-TABLE.
   03 I-NOTES-ARR PIC S9(4) COMP-5 OCCURS 5 TIMES.
....


* Execute query
....
EXEC SQL
SELECT substring(title, 1, 64), notes, pub_name,
            city, state
     INTO :HOST-STRUCTURE-M1:I-NOTES-ARR
     FROM titles, publishers
     WHERE titles.pub_id = publishers.pub_id
     AND title_id = :USER-TITLEID
END-EXEC.
....

Example 2 This is an example declaring indicator structures and executing a query on the indicator structures:

* Declare variables
....
01 HOST-STRUCTURE-M1.
   03 M-TITLE PIC X(64).
   03 M-NOTES PIC X(200).
   03 M-PUBNAME PIC X(40).
   03 M-PUBCITY PIC X(20).
   03 M-PUBSTATE PIC X(2).

01 INDICATOR-STRUCTURE-I1.
   03 I-TITLE PIC S9(4) COMP-5. 
   03 I-NOTES PIC S9(4) COMP-5.
   03 I-PUBNAME PIC S9(4) COMP-5.
   03 I-PUBCITY PIC S9(4) COMP-5.
   03 I-PUBSTATE PIC S9(4) COMP-5.
....

* Execute query
....
EXEC SQL
SELECT substring(title, 1, 64), notes, pub_name, city,
       state
    INTO :HOST-STRUCTURE-M1:INDICATOR-STRUCTURE-I1
    FROM titles, publishers
    WHERE titles.pub_id = publishers.pub_id
    AND title_id = :USER-TITLEID
END-EXEC.

When using structs and arrays as indicator variables:

• The number of elements in the indicator array or struct must be exactly the same as the number of elements in the host variable structure. A mismatch causes cobpre or cobpre64 to stop processing, and code is not generated.

• The columns in the SELECT list must match by sequence, and datatype, the chosen structure name in the INTO list. A mismatch causes ct_bind() runtime errors and stops processing.

You cannot mix singleton host variables or singleton indicator variables with hostvar structures, and indicator arrays or structures.