Sybase Adaptive Server Anywhere - Page 400

ALLOCATE DESCRIPTOR statement [ESQL]
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if( !db_init( &sqlca ) ) {
return 1;
}
db_string_connect( &sqlca,
"UID=dba;PWD=sql;DBF=d:\\asa6\\sample.db");
EXEC SQL ALLOCATE DESCRIPTOR sqlda1 WITH MAX 25;
EXEC SQL PREPARE :stmt FROM
’SELECT * FROM employee’;
EXEC SQL DECLARE curs CURSOR FOR :stmt;
EXEC SQL OPEN curs;
EXEC SQL DESCRIBE :stmt into sqlda1;
EXEC SQL GET DESCRIPTOR sqlda1 :numcols=COUNT;
// how many columns?
if( numcols > 25 ) {
// reallocate if necessary
EXEC SQL DEALLOCATE DESCRIPTOR sqlda1;
EXEC SQL ALLOCATE DESCRIPTOR sqlda1
WITH MAX :numcols;
EXEC SQL DESCRIBE :stmt into sqlda1;
}
type = DT_STRING; // change the type to string
EXEC SQL SET DESCRIPTOR sqlda1 VALUE 2 TYPE =
:type;
fill_sqlda( sqlda1 );
// allocate space for the variables
EXEC SQL FETCH ABSOLUTE 1 curs
USING DESCRIPTOR sqlda1;
EXEC SQL GET DESCRIPTOR sqlda1
VALUE 2 :string = DATA;
printf("name = %s", string );
EXEC SQL DEALLOCATE DESCRIPTOR sqlda1;
EXEC SQL CLOSE curs;
EXEC SQL DROP STATEMENT :stmt;
db_string_disconnect( &sqlca, "" );
db_fini( &sqlca );
return 0;
}