diff options
Diffstat (limited to 'sql/item.h')
| -rw-r--r-- | sql/item.h | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/sql/item.h b/sql/item.h index 68fa013647c..116dc86390c 100644 --- a/sql/item.h +++ b/sql/item.h @@ -310,6 +310,7 @@ public: class st_select_lex; class Item_ident :public Item { +protected: /* We have to store initial values of db_name, table_name and field_name to be able to restore them during cleanup() because they can be @@ -356,13 +357,21 @@ public: :Item_ident(db_par,table_name_par,field_name_par), field(0), result_field(0) { collation.set(DERIVATION_IMPLICIT); } - // Constructor need to process subselect with temporary tables (see Item) + /* + Constructor needed to process subselect with temporary tables (see Item) + */ Item_field(THD *thd, Item_field *item); /* - Constructor used inside setup_wild(), ensures that field and table - names will live as long as Item_field (important in prep. stmt.) + Constructor used inside setup_wild(), ensures that field, table, + and database names will live as long as Item_field (this is important + in prepared statements). */ Item_field(THD *thd, Field *field); + /* + If this constructor is used, fix_fields() won't work, because + db_name, table_name and column_name are unknown. It's necessary to call + reset_field() before fix_fields() for all fields created this way. + */ Item_field(Field *field); enum Type type() const { return FIELD_ITEM; } bool eq(const Item *item, bool binary_cmp) const; @@ -373,6 +382,7 @@ public: longlong val_int_result(); String *str_result(String* tmp); bool send(Protocol *protocol, String *str_arg); + void reset_field(Field *f); bool fix_fields(THD *, struct st_table_list *, Item **); void make_field(Send_field *tmp_field); int save_in_field(Field *field,bool no_conversions); |