+ if ( $op eq '=' ) {
+ if ( driver_name =~ /^Pg$/i ) {
+ qq-( $_ IS NULL OR $_ = '' )-;
+ } else {
+ qq-( $_ IS NULL OR $_ = "" )-;
+ }
+ } elsif ( $op eq '!=' ) {
+ if ( driver_name =~ /^Pg$/i ) {
+ qq-( $_ IS NOT NULL AND $_ != '' )-;
+ } else {
+ qq-( $_ IS NOT NULL AND $_ != "" )-;
+ }