diff options
Diffstat (limited to 'sql/item.cc')
| -rw-r--r-- | sql/item.cc | 47 |
1 files changed, 46 insertions, 1 deletions
diff --git a/sql/item.cc b/sql/item.cc index 0c5b6450b4a..5091ea87bee 100644 --- a/sql/item.cc +++ b/sql/item.cc @@ -299,7 +299,8 @@ bool DTCollation::aggregate(DTCollation &dt) return 0; } -Item_field::Item_field(Field *f) :Item_ident(NullS,f->table_name,f->field_name) +Item_field::Item_field(Field *f) + :Item_ident(NullS,f->table_name,f->field_name), item_equal(0) { set_field(f); collation.set(DERIVATION_IMPLICIT); @@ -313,6 +314,7 @@ Item_field::Item_field(THD *thd, Item_field &item) result_field(item.result_field) { collation.set(DERIVATION_IMPLICIT); + item_equal= item.item_equal; } void Item_field::set_field(Field *field_par) @@ -969,6 +971,49 @@ bool Item_field::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref) return 0; } +Item_equal *Item_field::find_item_equal(COND_EQUAL *cond_equal) +{ + Item_equal *item= 0; + while (cond_equal) + { + List_iterator_fast<Item_equal> li(cond_equal->current_level); + while ((item= li++)) + { + if (item->contains(field)) + return item; + } + cond_equal= cond_equal->parent_level; + } + return item; +} + +Item *Item_field::equal_fields_propagator(byte *arg) +{ + COND_EQUAL *cond_equal= (COND_EQUAL *) arg; + item_equal= find_item_equal(cond_equal); + Item *item= 0; + if (item_equal) + item= item_equal->get_const(); + if (item) + item->fixed= 0; + else + item= this; + return item; +} + +bool Item_field::replace_equal_field_processor(byte *arg) +{ + if (item_equal) + { + Item_field *subst= item_equal->get_first(); + if (subst && !field->eq(subst->field)) + { + field= subst->field; + return 0; + } + } + return 0; +} void Item::init_make_field(Send_field *tmp_field, enum enum_field_types field_type) |