diff options
Diffstat (limited to 'sql/item_cmpfunc.cc')
| -rw-r--r-- | sql/item_cmpfunc.cc | 34 |
1 files changed, 30 insertions, 4 deletions
diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc index c0d3b14b71b..325e4ac219e 100644 --- a/sql/item_cmpfunc.cc +++ b/sql/item_cmpfunc.cc @@ -2901,11 +2901,35 @@ void Item_func_case::agg_num_lengths(Item *arg) } +/** + Check if (*place) and new_value points to different Items and call + THD::change_item_tree() if needed. + + This function is a workaround for implementation deficiency in + Item_func_case. The problem there is that the 'args' attribute contains + Items from different expressions. + + The function must not be used elsewhere and will be remove eventually. +*/ + +static void change_item_tree_if_needed(THD *thd, + Item **place, + Item *new_value) +{ + if (*place == new_value) + return; + + thd->change_item_tree(place, new_value); +} + + void Item_func_case::fix_length_and_dec() { Item **agg; uint nagg; uint found_types= 0; + THD *thd= current_thd; + if (!(agg= (Item**) sql_alloc(sizeof(Item*)*(ncases+1)))) return; @@ -2930,9 +2954,10 @@ void Item_func_case::fix_length_and_dec() Some of the items might have been changed to Item_func_conv_charset. */ for (nagg= 0 ; nagg < ncases / 2 ; nagg++) - args[nagg * 2 + 1]= agg[nagg]; + change_item_tree_if_needed(thd, &args[nagg * 2 + 1], agg[nagg]); + if (else_expr_num != -1) - args[else_expr_num]= agg[nagg++]; + change_item_tree_if_needed(thd, &args[else_expr_num], agg[nagg++]); } else collation.set_numeric(); @@ -2992,9 +3017,10 @@ void Item_func_case::fix_length_and_dec() arrray, because some of the items might have been changed to converters (e.g. Item_func_conv_charset, or Item_string for constants). */ - args[first_expr_num]= agg[0]; + change_item_tree_if_needed(thd, &args[first_expr_num], agg[0]); + for (nagg= 0; nagg < ncases / 2; nagg++) - args[nagg * 2]= agg[nagg + 1]; + change_item_tree_if_needed(thd, &args[nagg * 2], agg[nagg + 1]); } for (i= 0; i <= (uint)TIME_RESULT; i++) |