527
528
save_read_set= sort_form->read_set;
528
529
save_write_set= sort_form->write_set;
529
530
/* Set up temporary column read map for columns used by sort */
531
532
/* Temporary set for register_used_fields and register_field_in_read_map */
532
533
sort_form->read_set= &sort_form->tmp_set;
533
534
register_used_fields(param);
534
535
if (select && select->cond)
535
536
select->cond->walk(&Item::register_field_in_read_map, 1,
536
537
(unsigned char*) sort_form);