SQL Programming Manual for Pascal

NonStop SQL Statements and Directives
HP NonStop SQL Programming Manual for Pascal—528614-001
3-27
INVOKE With the NULL STRUCTURE Clause
LAST_NAME CHARACTER(20) NO DEFAULT NOT NULL,
RETIRE_DATE DATETIME YEAR TO DAY,
PRIMARY KEY EMPNUM
)
CATALOG \SYS.$VOL.TESTCAT;
INVOKE statements on this table produce output as follows: the PREFIX clause
causes INVOKE to generate indicator variables with the prefix IND_VAR; in the NULL
STRUCTURE version, indicator variables are named INDICATOR.
The INVOKE directive is:
EXEC SQL INVOKE EMPTBL PREFIX IND_VAR_;
NonStop SQL generates this record description:
{* Record Definition for table \SYS.$VOL.SUBVOL.EMPTBL *}
{* Definition current at 16:06:49 - 05/17/91 *}
type
emptbl_type = record
empnum : cardinal;
ind_var_first_name : int16;
first_name : fstring(15);
last_name : fstring(20);
ind_var_retire_date : int16;
retire_date : fstring(10);
end;
INVOKE With the NULL STRUCTURE Clause
This example uses the INVOKE directive with the NULL STRUCTURE clause. The
NULL STRUCTURE clause, which causes columns that contain null values to be
defined as structures, assigns the name INDICATOR to all indicator variables in the
sample structure template.
Statement in a Pascal program:
EXEC SQL INVOKE EMPTBL NULL STRUCTURE;
NonStop SQL generates this record description:
{* Record Definition for table \SYS.$VOL.SUBVOL.EMPTBL *}
{* Definition current at 16:07:00 - 05/17/91 *}
type
emptbl_type = record
empnum : cardinal;
first_name : record
indicator : int16;
valu : fstring(15);
end;
last_name : fstring(20);
retire_date : record
indicator : int16;
valu : fstring(10);