+ // Locally at least, (my local is a rather old version of mysql)
+ // mysql seems to filesort if there is both an equality
+ // (but not for an inequality) condition on cl_collation in the
+ // WHERE and it is also the first item in the ORDER BY.
+ if ( $this->hasOption( 'previous-collation' ) ) {
+ $orderBy = 'cl_to, cl_type, cl_from';
+ } else {
+ $orderBy = 'cl_collation, cl_to, cl_type, cl_from';
+ }