Retrieves attribute information about dynamic parameter markers and select column list attributes and data from a SQL descriptor.
For a list of SQL descriptor datatype codes, see Table 9-5.
exec sql get descriptor descriptor_name
{:host_variable = count |
value item_number :host_variable = item_name
[, :host_variable = item_name]...} end-exec
The name of the SQL descriptor that contains information about the dynamic parameter markers or return columns in a prepared statement.
A variable defined in a declare section.
The number of dynamic parameters retrieved.
A number specifying the nth dynamic parameter marker or select column, for which get descriptor is to retrieve information.
The name of an attribute to be retrieved. See Table 9-3 for details.
Value |
Description |
|---|---|
data |
Value for the dynamic parameter marker or target associated with the specified SQL descriptor. If indicator is negative, this field is undefined. |
indicator |
Value for the indicator parameter associated with the dynamic parameter marker or target. |
length |
The length, in characters, of the dynamic parameter marker of target for the specified SQL descriptor. |
name |
The name of the specified SQL descriptor containing information about the dynamic parameter markers. |
nullable |
Equals 0 if the dynamic parameter marker can accept a null value; otherwise, equals 1. |
precision |
An integer specifying the total number of digits of precision for the CS_NUMERIC variable. |
returned_length |
The length of character types of the values from the select column list. |
scale |
An integer specifying the total number of digits after the decimal point for the CS_NUMERIC variable. |
type |
The datatype of this column (item number) in the row. For values, see Table 9-5. |
EXEC SQL BEGIN DECLARE SECTION END-EXEC.
01 QUERY PIC X(100).
01 CHARBUF PIC X(100).
01 NUMCOLS PIC S9(9) COMP.
01 COLNUM PIC S9(9) COMP.
01 COLTYPE PIC S9(9) COMP.
01 INTBUF PIC S9(9).
EXEC SQL END DECLARE SECTION END-EXEC.
...
DISPLAY "ENTER A SELECT STATEMENT :"
ACCEPT QUERY.
EXEC SQL ALLOCATE DESCRIPTOR big_desc WITH MAX 256 END-EXEC.
EXEC SQL PREPARE dynstmt FROM :QUERY END-EXEC.
EXEC SQL EXECUTE dynstmt INTO SQL DESCRIPTOR big_desc END-EXEC.
EXEC SQL GET DESCRIPTOR big_desc :NUMCOLS = COUNT END-EXEC.
MOVE 1 TO COLNUM.
PERFORM GET-DESC-LOOP UNTIL COLNUM > NUMCOLS.
EXEC SQL DEALLOCATE PREPARE dynstmt END-EXEC.
EXEC SQL DEALLOCATE DESCRIPTOR big_desc END-EXEC.
...
GET-DESC-LOOP.
EXEC SQL GET DESCRIPTOR big_desc
VALUE :COLNUM
:COLTYPE = TYPE END-EXEC
* Check the type data returned and store in appropriate host variables.
IF COLTYPE = 4
DISPLAY "INTEGER DATA! "
EXEC SQL GET DESCRIPTOR big_desc
VALUE :COLNUM :INTBUF = DATA END-EXEC
ELSE
IF COLTYPE = 1
DISPLAY "CHARACTER DATA! "
EXEC SQL GET DESCRIPTOR big_desc
VALUE :COLNUM :CHARBUF = DATA END-EXEC
* Handle other data types accordingly or store them all as characters.
...
ADD 1 TO COLUMN.
END-GET-DESC-LOOP.
The get descriptor statement returns information about the number or attributes of dynamic parameters specified or the select list columns in a prepared statement.
This statement should be executed after a describe input, describe output, execute, or fetch (dynamic) statement has been issued.
It is not possible to retrieve data, indicator, or returned_length until the data associated with the descriptor is retrieved from the server by an execute statement or fetch statement.
describe input, describe output, fetch, set descriptor
