diff options
Diffstat (limited to 'sql/sql_lex.h')
| -rw-r--r-- | sql/sql_lex.h | 112 |
1 files changed, 55 insertions, 57 deletions
diff --git a/sql/sql_lex.h b/sql/sql_lex.h index a48aa5721e4..adf452376a7 100644 --- a/sql/sql_lex.h +++ b/sql/sql_lex.h @@ -118,6 +118,12 @@ enum olap_type subselects or derived tables) for ordinary select_lex - list of all select_lex (for group operation like correcting list of opened tables) + - if unit contain several selects (union) then it have special + select_lex called fake_select_lex. It used for storing global parameters + and executing union. subqueries of global ORDER BY clause will be + attached to this fake_select_lex, which will allow them correctly + resolve fields of 'upper' union and other more outer selects. + for example for following query: select * @@ -138,6 +144,7 @@ enum olap_type main unit + fake0 select1 select2 select3 |^^ |^ s||| ||master @@ -146,7 +153,8 @@ enum olap_type v|||master slave || e||+-------------------------+ || V| neighbor | V| - unit 1.1<==================>unit1.2 unit2.1 + unit1.1<+==================>unit1.2 unit2.1 + fake1.1 fake2.1 select1.1.1 select 1.1.2 select1.2.1 select2.1.1 select2.1.2 |^ || @@ -158,13 +166,14 @@ enum olap_type relation in main unit will be following: main unit - |^^^ - |||| - |||+------------------------------+ - ||+--------------+ | - slave||master | | - V| neighbor | neighbor | - select1<========>select2<========>select3 + |^^^^|fake_select_lex + |||||+--------------------------------------------+ + ||||+--------------------------------------------+| + |||+------------------------------+ || + ||+--------------+ | || + slave||master | | || + V| neighbor | neighbor | master|V + select1<========>select2<========>select3 fake0 list of all select_lex will be following (as it will be constructed by parser): @@ -199,17 +208,6 @@ public: ulong options; enum sub_select_type linkage; - SQL_LIST order_list; /* ORDER clause */ - List<List_item> expr_list; - List<List_item> when_list; /* WHEN clause (expression) */ - ha_rows select_limit, offset_limit; /* LIMIT clause parameters */ - // Arrays of pointers to top elements of all_fields list - Item **ref_pointer_array; - - uint select_items; /* number of items in select_list */ - uint cond_count; /* number of arguments of and/or/xor in where/having */ - enum_parsing_place parsing_place; /* where we are parsing expression */ - bool with_sum_func; /* sum function indicator */ bool dependent; /* dependent from outer select subselect */ bool uncacheable; /* result of this query can't be cached */ bool no_table_names_allowed; /* used for global order by */ @@ -226,18 +224,13 @@ public: virtual void init_select(); void include_down(st_select_lex_node *upper); void include_neighbour(st_select_lex_node *before); + void include_standalone(st_select_lex_node *sel, st_select_lex_node **ref); void include_global(st_select_lex_node **plink); void exclude(); - virtual st_select_lex* select_lex(); - virtual bool add_item_to_list(THD *thd, Item *item); - bool add_order_to_list(THD *thd, Item *item, bool asc); - virtual bool add_group_to_list(THD *thd, Item *item, bool asc); - virtual bool add_ftfunc_to_list(Item_func_match *func); - virtual st_select_lex_unit* master_unit()= 0; virtual st_select_lex* outer_select()= 0; - virtual st_select_lex_node* return_after_parsing()= 0; + virtual st_select_lex* return_after_parsing()= 0; virtual bool set_braces(bool value); virtual bool inc_in_sum_expr(); @@ -247,16 +240,7 @@ public: virtual List<String>* get_use_index(); virtual List<String>* get_ignore_index(); virtual ulong get_table_join_options(); - virtual TABLE_LIST *add_table_to_list(THD *thd, Table_ident *table, - LEX_STRING *alias, - ulong table_options, - thr_lock_type flags= TL_UNLOCK, - List<String> *use_index= 0, - List<String> *ignore_index= 0); virtual void set_lock_for_tables(thr_lock_type lock_type) {} - void mark_as_dependent(st_select_lex *last); - - bool test_limit(); friend class st_select_lex_unit; friend bool mysql_new_select(struct st_lex *lex, bool move_down); @@ -293,14 +277,17 @@ public: Pointer to 'last' select or pointer to unit where stored global parameters for union */ - st_select_lex_node *global_parameters; + st_select_lex *global_parameters; //node on wich we should return current_select pointer after parsing subquery - st_select_lex_node *return_to; + st_select_lex *return_to; /* LIMIT clause runtime counters */ ha_rows select_limit_cnt, offset_limit_cnt; /* not NULL if union used in subselect, point to subselect item */ Item_subselect *item; + /* thread handler */ THD *thd; + /* fake SELECT_LEX for union processing */ + st_select_lex *fake_select_lex; uint union_option; @@ -312,11 +299,10 @@ public: st_select_lex* first_select() { return (st_select_lex*) slave; } st_select_lex* first_select_in_union() { - return (slave && slave->linkage == GLOBAL_OPTIONS_TYPE) ? - (st_select_lex*) slave->next : (st_select_lex*) slave; + return (st_select_lex*) slave; } st_select_lex_unit* next_unit() { return (st_select_lex_unit*) next; } - st_select_lex_node* return_after_parsing() { return return_to; } + st_select_lex* return_after_parsing() { return return_to; } void exclude_level(); /* UNION methods */ @@ -354,6 +340,19 @@ public: List<Item_func_match> ftfunc_list_alloc; JOIN *join; /* after JOIN::prepare it is pointer to corresponding JOIN */ const char *type; /* type of select for EXPLAIN */ + + SQL_LIST order_list; /* ORDER clause */ + List<List_item> expr_list; + List<List_item> when_list; /* WHEN clause (expression) */ + ha_rows select_limit, offset_limit; /* LIMIT clause parameters */ + // Arrays of pointers to top elements of all_fields list + Item **ref_pointer_array; + + uint select_items; /* number of items in select_list */ + uint cond_count; /* number of arguments of and/or/xor in where/having */ + enum_parsing_place parsing_place; /* where we are parsing expression */ + bool with_sum_func; /* sum function indicator */ + ulong table_join_options; uint in_sum_expr; uint select_number; /* number of select (used for EXPLAIN) */ @@ -369,8 +368,6 @@ public: before passing to handle_select) */ bool insert_select; - /* TRUE for fake select, which used in UNION processing */ - bool fake_select; void init_query(); void init_select(); @@ -389,31 +386,33 @@ public: { return &link_next; } - st_select_lex_node* return_after_parsing() + st_select_lex* return_after_parsing() { return master_unit()->return_after_parsing(); } + void mark_as_dependent(st_select_lex *last); + bool set_braces(bool value); bool inc_in_sum_expr(); uint get_in_sum_expr(); - st_select_lex* select_lex(); bool add_item_to_list(THD *thd, Item *item); bool add_group_to_list(THD *thd, Item *item, bool asc); bool add_ftfunc_to_list(Item_func_match *func); - - TABLE_LIST* get_table_list(); - List<Item>* get_item_list(); - List<String>* get_use_index(); - List<String>* get_ignore_index(); - ulong get_table_join_options(); + bool add_order_to_list(THD *thd, Item *item, bool asc); TABLE_LIST* add_table_to_list(THD *thd, Table_ident *table, LEX_STRING *alias, ulong table_options, thr_lock_type flags= TL_UNLOCK, List<String> *use_index= 0, List<String> *ignore_index= 0); + + TABLE_LIST* get_table_list(); + List<Item>* get_item_list(); + List<String>* get_use_index(); + List<String>* get_ignore_index(); + ulong get_table_join_options(); void set_lock_for_tables(thr_lock_type lock_type); inline void init_order() { @@ -422,15 +421,14 @@ public: order_list.next= (byte**) &order_list.first; } + bool test_limit(); + friend void mysql_init_query(THD *thd); - st_select_lex(struct st_lex *lex); - st_select_lex() :fake_select(0) {} - void make_empty_select(st_select_lex *last_select) + st_select_lex() {} + void make_empty_select() { - select_number=INT_MAX; init_query(); init_select(); - include_neighbour(last_select); } }; typedef class st_select_lex SELECT_LEX; @@ -445,7 +443,7 @@ typedef struct st_lex SELECT_LEX_UNIT unit; /* most upper unit */ SELECT_LEX select_lex; /* first SELECT_LEX */ /* current SELECT_LEX in parsing */ - SELECT_LEX_NODE *current_select; + SELECT_LEX *current_select; /* list of all SELECT_LEX */ SELECT_LEX *all_selects_list; uchar *ptr,*tok_start,*tok_end,*end_of_query; @@ -517,7 +515,7 @@ typedef struct st_lex but we should merk all subselects as uncacheable from current till most upper */ - SELECT_LEX_NODE *sl; + SELECT_LEX *sl; SELECT_LEX_UNIT *un; for (sl= current_select, un= sl->master_unit(); un != &unit; |