Use SQL descriptor areas in REXX applications

The following statements can use an SQLDA:

• EXECUTE...USING DESCRIPTOR descriptor-name
• FETCH...USING DESCRIPTOR descriptor-name
• OPEN...USING DESCRIPTOR descriptor-name
• CALL...USING DESCRIPTOR descriptor-name
• DESCRIBE statement-name INTO descriptor-name
• DESCRIBE TABLE host-variable INTO descriptor-name

Unlike the SQLCA, more than one SQLDA can be in a procedure, and an SQLDA can have any valid name.

Each SQLDA consists of a set of REXX variables with a common stem, where the name of the stem is the descriptor-name from the appropriate SQL statements. This must be a simple stem; that is, the stem itself must not contain any periods. The SQL/REXX interface automatically provides the fields of the SQLDA for each unique descriptor name. An INCLUDE SQLDA statement is not required and is not allowed.

The SQL/REXX interface uses the SQLDA in a manner consistent with the typical SQL usage. However, the SQL/REXX interface maintains the fields of the SQLDA in separate variables rather than in a contiguous data area.

The following variables are returned to the application after a DESCRIBE, a DESCRIBE TABLE, or a PREPARE INTO statement:

stem.n.SQLNAME

The name of the nth column in the result table.

The following variables must be provided by the application before an EXECUTE...USING DESCRIPTOR, an OPEN...USING DESCRIPTOR, a CALL...USING DESCRIPTOR, or a FETCH...USING DESCRIPTOR statement. They are returned to the application after a DESCRIBE, a DESCRIBE TABLE, or a PREPARE INTO statement:

stem.SQLD

Number of variable elements that the SQLDA actually contains.

stem.n.SQLTYPE

An integer representing the data type of the nth element (for example, the first element is in stem.1.SQLTYPE).

The following data types are not allowed:

400/401

NUL-terminated graphic string

404/405

BLOB host variable

408/409

CLOB host variable

412/413

DBCLOB host variable

460/461

NUL-terminated character string

476/477

PASCAL L-string

496/497

Large integer (where scale is greater than 0)

500/501

Small integer (where scale is greater than 0)

504/505

DISPLAY SIGN LEADING SEPARATE

904/905

ROWID

908/909

VARBINARY host variable

912/913

BINARY host variable

916/917

BLOB file reference variable

920/921

CLOB file reference variable

924/925

DBCLOB file reference variable

960/961

BLOB locator

964/965

CLOB locator

968/969

DBCLOB locator

stem.n.SQLLEN

If SQLTYPE does not indicate a DECIMAL or NUMERIC data type, the maximum length of the data contained in stem.n.SQLDATA.

stem.n.SQLLEN.SQLPRECISION

If the data type is DECIMAL or NUMERIC, this contains the precision of the number.

stem.n.SQLLEN.SQLSCALE

If the type is DECIMAL or NUMERIC, this contains the scale of the number.

stem.n.SQLCCSID

The CCSID of the nth column of the data.

The following variables must be provided by the application before an EXECUTE...USING DESCRIPTOR or an OPEN...USING DESCRIPTOR statement, and they are returned to the application after a FETCH...USING DESCRIPTOR statement. They are not used after a DESCRIBE, a DESCRIBE TABLE, or a PREPARE INTO statement:

stem.n.SQLDATA

This contains the input value supplied by the application, or the output value fetched by SQL.

This value is converted to the attributes specified in SQLTYPE, SQLLEN, SQLPRECISION, and SQLSCALE.

stem.n.SQLIND

If the input or output value is null, this is a negative number.