SQLDA

The SQL Descriptor Area (SQLDA) is a data structure used to describe variable data passed as part of a dynamic SQL statement.

The SQLDA consists of the following fields:

Field	Data type	Meaning
SQLDAID	CHARACTER(8)	Set to SQLDA* on a DESCRIBE
SQLN	INTEGER	Maximum number of SQLVAR occurrences
SQLD	INTEGER	Actual number of SQLVAR occurrences: 0—Not a SELECT statement 1 through SQLN—Number of columns Greater than SQLN—Not enough SQLVAR entries
SQLVAR		Structure occurring SQLN times

The structure SQLVAR in the SQLDA consists of the following fields:

Field	Data type	Meaning
SQLLEN	INTEGER	Length (Additional information provided under "SQLLEN")
SQLTYPE	SMALLINT	Column data type (Additional information provided under "SQLTYPE")
SQLSCALE	SMALLINT	Scale (for exact numeric data types) (Additional information provided under "SQLSCALE")
SQLPRECISION	SMALLINT	Precision (Additional information provided under "SQLPRECISION")
SQLALN	SMALLINT	Data alignment flag (Additional information provided under "SQLALN and SQLNALN ")
SQLNALN	SMALLINT	Null indicator alignment flag (Additional information provided under "SQLALN and SQLNALN ")
SQLNULL	SMALLINT	Length of null indicator (Additional information provided under "SQLNULL")
SQLNAME	CHARACTER(32)	Column name

The SQLDA can be used by an application program in the following ways:

As output on a DESCRIBE or PREPARE statement as the location into which the DBMS returns the descriptions of selected columns.
As input on a FETCH statement to describe the target area for selected columns.