Multiple Statements Usage

For example:

my $sth = $dbh->prepare("
	insert into publishers (col1, col2, col3) values (10, 12, 14)
	insert into publishers (col1, col2, col3) values (1, 2, 4)
	insert into publishers (col1, col2, col3) values (11, 13, 15)
	");
my $rc = $sth->execute();

If any of these statements fail, sth->execute() returns undef. If AutoCommit is on, statements that complete successfully may have inserted data in the table, which may not be the result you expect or want.

Multiple Result Sets

The Perl driver allows you to prepare multiple statements with one call and execute them with another single call. For example, executing a stored procedure that contains multiple selects returns multiple result sets.

Results of multiple statements prepared with one call are returned to the client as a single stream of data. Each distinct set of results is treated as a normal single result set, which means that the statement handle's fetch() method returns undef at the end of each set.

The CT-Lib API ct_fetch() returns CS_END_RESULTS that the driver converts to undef after the last rows have been retrieved.

The driver allows the application to obtain the result type by checking sth->{syb_result_type}. You can then use the sth->{syb_more_results} statement handle attribute to determine if there are additional result sets still to be returned. The (numerical) value returned by sth->{syb_results_type} is one of:

Example for multiple result sets:

do {
	while($a = $sth->fetch) {
	..for example, display data..
	} 
} while($sth->{syb_more_results});

Sybase recommends that you use this if you expect multiple result sets.

Multiple Active Statements on a DatabaseHandle (dbh)

There can be multiple active statements on a single database handle by opening a new connection in the $dbh->prepare() method if there is already an active statement handle on this $dbh.

The dbh->{syb_no_child_con} attribute controls whether this feature is on or off. By default, DatabaseHandle is off, which indicates that multiple statement handles are supported. If it is on, multiple statements on the same database handle are disabled.