ok, i don't think i've done anything stupid, yet stupid things keep happening. here's the deal.

for the convenience of my fellow perl haxors at my company, i have created a module which centralises a whole lot of basic code to handle http sessioning, cgi parameter-handling, db connections and the like. no probs.

what's got me stuped is the following routine -- given an sql statement, it prepares it, executes it and returns a statement handle (if a select statement was given), or number of insert rows/update rows/delete rows otherwise.

the problem is that the routine never returns an actual $sth statement handle, even when a given sql query is successful. within the routine, printing $sth prints the expected DBI::st object, but in client code, the returned $sth is always '', the null string.

here is the routine: 

sub do_sql
{
    my $this = shift;
    my $sql = shift || return;

    my $dbh = $this->get_db_connection();
    eval {
        if ( $sql =~ /^select/i ) {
            $this->log_internal_notice("executing sql query: $sql");
            my $sth = $dbh->prepare( $sql );
            my $nmb = $sth->execute();

            $this->log_internal_notice(
                $nmb == 1
                ?   "1 result"
                :   "$nmb results"
            );

            return $sth;
        }
        else {
            $this->log_notice("executing non-select sql: $sql");
            return $dbh->do( $sql );
        }
    };
    if ( $@ ) {
        $this->log_warning("Caught exception executing sql: $@");
        return;
    }
}

[download]

and here is some client code: 

    my $sth = $my_module_object->do_sql( $sql ) ||
        return "<p><i>There are currently no experiment steps in this 
+experiment</i></p>";

[download]

Any ideas?

All replies much appreciated...
dirty

In reply to calling all DBI wizards... by d_i_r_t_y

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