diff options
| -rw-r--r-- | sql/item_cmpfunc.cc | 18 | ||||
| -rw-r--r-- | sql/opt_subselect.cc | 14 | ||||
| -rw-r--r-- | sql/sql_join_cache.cc | 46 | ||||
| -rw-r--r-- | sql/sql_select.cc | 67 | ||||
| -rw-r--r-- | sql/sql_select.h | 23 |
5 files changed, 54 insertions, 114 deletions
diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc index 8d90da50e0d..ad8529ed0bb 100644 --- a/sql/item_cmpfunc.cc +++ b/sql/item_cmpfunc.cc @@ -5733,26 +5733,10 @@ Item_field* Item_equal::get_first(Item_field *field) It's a field from an materialized semi-join. We can substitute it only for a field from the same semi-join. */ -#if 0 - psergey3:remove: - JOIN_TAB *first; - JOIN *join= field_tab->join; - int tab_idx= field_tab - field_tab->join->join_tab; - - /* Find the first table of this semi-join nest */ - for (int i= tab_idx; i >= (int)join->const_tables; i--) - { - if (join->join_tab[i].table->map & emb_nest->sj_inner_tables) - first= join->join_tab + i; - else - // Found first tab that doesn't belong to current SJ. - break; - } -#endif + /* Find an item to substitute for. */ while ((item= it++)) { - //if (item->field->table->reginfo.join_tab >= first) if (item->field->table->pos_in_table_list->embedding == emb_nest) { /* diff --git a/sql/opt_subselect.cc b/sql/opt_subselect.cc index 97a0a00f613..e6898db53e3 100644 --- a/sql/opt_subselect.cc +++ b/sql/opt_subselect.cc @@ -45,13 +45,13 @@ exception that we don't care how many matches a row from outer_tbl has in inner_tbl. - In SQL, that translates into following: a semi-join subquery is an IN - subquery that is an AND-part of the WHERE/ON clause. + In SQL terms: a semi-join subquery is an IN subquery that is an AND-part of + the WHERE/ON clause. 2. General idea about semi-join execution ----------------------------------------- - We can execute semi-join in a way similar to inner join, with exception that - we need to somehow ensure that we do not generate record combinations that + We can execute semi-join in a way similar to inner join, with exception that + we need to somehow ensure that we do not generate record combinations that differ only in rows of inner tables. There is a number of different ways to achieve this property, implemented by a number of semi-join execution strategies. @@ -3957,8 +3957,8 @@ static void remove_subq_pushed_predicates(JOIN *join, Item **where) bool join_tab_execution_startup(JOIN_TAB *tab) { - DBUG_ENTER("join_tab_execution_startup"); Item_in_subselect *in_subs; + DBUG_ENTER("join_tab_execution_startup"); if (tab->table->pos_in_table_list && (in_subs= tab->table->pos_in_table_list->jtbm_subselect)) { @@ -3995,13 +3995,9 @@ bool join_tab_execution_startup(JOIN_TAB *tab) if ((rc= sub_select(join, join_tab, FALSE/* no EOF */)) < 0 || (rc= sub_select(join, join_tab, TRUE/* now EOF */)) < 0) { - //psergey3-todo: set sjm->materialized=TRUE here, too?? join->return_tab= save_return_tab; DBUG_RETURN(rc); /* it's NESTED_LOOP_(ERROR|KILLED)*/ } - /* - Ok, materialization finished. Initialize the access to the temptable - */ join->return_tab= save_return_tab; sjm->materialized= TRUE; } diff --git a/sql/sql_join_cache.cc b/sql/sql_join_cache.cc index a4db80b29a1..5db5928fba1 100644 --- a/sql/sql_join_cache.cc +++ b/sql/sql_join_cache.cc @@ -158,42 +158,6 @@ JOIN_TAB *next_linear_tab(JOIN* join, JOIN_TAB* tab, bool include_bush_roots); void JOIN_CACHE::calc_record_fields() { - //psergey4-todo: prev_cache, or - // - first non-const table if on top level - // - first table inside SJM nest if within sjm nest - // this->join_tab is 'our' join_tab - - // No. the right idea: start from ... and walk to the current join_tab - /// with an iterator, skipping - // join nests (can do so for now) - - /* - The above sucks, too. - The right idea: - - for SJM-inner tables, walk only within the nest - - for SJM-outer tables, use all preceding tables, including inner ones. - eof - */ - -/* JOIN_TAB *tab = prev_cache ? prev_cache->join_tab : - join->join_tab+join->const_tables; -*/ - -/* JOIN_TAB *tab; - if (prev_cache) - tab= prev_cache->join_tab; - else - { - if (tab->bush_root_tab) - { - ; - } - else - { - / * top-level * / - tab= join->join_tab+join->const_tables; - } - }*/ JOIN_TAB *tab; if (prev_cache) tab= prev_cache->join_tab; @@ -201,12 +165,18 @@ void JOIN_CACHE::calc_record_fields() { if (join_tab->bush_root_tab) { - // inside SJM-Mat nest: pick first one + /* + If the tab we're attached to is inside an SJM-nest, start from the + first tab in that SJM nest + */ tab= join_tab->bush_root_tab->bush_children->start; } else { - // outside SJM-Mat nest: start from first non-const table + /* + The tab we're attached to is not inside an SJM-nest. Start from the + first non-const table. + */ tab= join->join_tab + join->const_tables; } } diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 3b3febcbc7a..a96e0538636 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -1011,10 +1011,10 @@ JOIN::optimize() { List_iterator<JOIN_TAB_RANGE> it(join_tab_ranges); JOIN_TAB_RANGE *jt_range; - bool first= TRUE; + uint first_tab_offs= const_tables; while ((jt_range= it++)) { - for (JOIN_TAB *tab= jt_range->start + (first ? const_tables : 0); + for (JOIN_TAB *tab= jt_range->start + first_tab_offs; tab < jt_range->end; tab++) { if (*tab->on_expr_ref) @@ -1025,7 +1025,7 @@ JOIN::optimize() (*tab->on_expr_ref)->update_used_tables(); } } - first= FALSE; + first_tab_offs= 0; } } @@ -1298,9 +1298,11 @@ JOIN::optimize() */ if (need_tmp || select_distinct || group_list || order) { - for (uint i = const_tables; i < tables; i++) - table[i]->prepare_for_position(); - + for (uint i= 0; i < tables; i++) + { + if (!(table[i]->map & const_table_map)) + table[i]->prepare_for_position(); + } } DBUG_EXECUTE("info",TEST_join(this);); @@ -5868,11 +5870,10 @@ JOIN_TAB *first_linear_tab(JOIN *join, bool after_const_tables) { JOIN_TAB *first= join->join_tab; if (after_const_tables) - first += join->const_tables; + first+= join->const_tables; if (first < join->join_tab + join->top_jtrange_tables) return first; - else - return NULL; + return NULL; } @@ -5888,24 +5889,24 @@ JOIN_TAB *first_linear_tab(JOIN *join, bool after_const_tables) to.) */ -JOIN_TAB *next_linear_tab(JOIN* join, JOIN_TAB* tab, bool include_bush_roots) //psergey2: added +JOIN_TAB *next_linear_tab(JOIN* join, JOIN_TAB* tab, bool include_bush_roots) { if (include_bush_roots && tab->bush_children) return tab->bush_children->start; + DBUG_ASSERT(!tab->last_leaf_in_bush || tab->bush_root_tab); if (tab->last_leaf_in_bush) tab= tab->bush_root_tab; if (tab->bush_root_tab) return ++tab; - if (++tab == join->join_tab + join->top_jtrange_tables /*join->join_tab_ranges.head()->end*/) + if (++tab == join->join_tab + join->top_jtrange_tables) return NULL; if (!include_bush_roots && tab->bush_children) - { tab= tab->bush_children->start; - } + return tab; } @@ -5929,12 +5930,12 @@ JOIN_TAB *next_linear_tab(JOIN* join, JOIN_TAB* tab, bool include_bush_roots) // */ -JOIN_TAB *next_depth_first_tab(JOIN* join, JOIN_TAB* tab) //psergey2: added +JOIN_TAB *next_depth_first_tab(JOIN* join, JOIN_TAB* tab) { bool start= FALSE; if (tab == NULL) { - /* This means we're starting. */ + /* This means we're starting the enumeration */ if (join->const_tables == join->top_jtrange_tables) return NULL; @@ -5944,8 +5945,12 @@ JOIN_TAB *next_depth_first_tab(JOIN* join, JOIN_TAB* tab) //psergey2: added if (tab->last_leaf_in_bush) return tab->bush_root_tab; + + /* Move to next tab in the array we're traversing*/ + if (!start) + tab++; - if ((start? tab: ++tab) == join->join_tab_ranges.head()->end) + if (tab == join->join_tab_ranges.head()->end) return NULL; /* End */ if (tab->bush_children) @@ -5955,7 +5960,7 @@ JOIN_TAB *next_depth_first_tab(JOIN* join, JOIN_TAB* tab) //psergey2: added } -static Item *null_ptr= NULL; +static Item * const null_ptr= NULL; /* Set up join struct according to the picked join order in @@ -6004,10 +6009,6 @@ get_best_combination(JOIN *join) fix_semijoin_strategies_for_picked_join_order(join); - /* - psergey2-todo: Here: switch to nested structure when copying. - */ - JOIN_TAB_RANGE *root_range= new JOIN_TAB_RANGE; root_range->start= join->join_tab; /* root_range->end will be set later */ @@ -6041,7 +6042,7 @@ get_best_combination(JOIN *join) j->ref.key_parts=0; j->loosescan_match_tab= NULL; //non-nulls will be set later j->use_join_cache= FALSE; - j->on_expr_ref= &null_ptr; + j->on_expr_ref= (Item**) &null_ptr; j->cache= NULL; /* @@ -6363,9 +6364,6 @@ JOIN::make_simple_join(JOIN *parent, TABLE *tmp_table) DBUG_RETURN(TRUE); /* purecov: inspected */ join_tab= parent->join_tab_reexec; - //psergey2: hopefully this is ok: - // join_tab_ranges.head()->start= join_tab; - // join_tab_ranges.head()->end= join_tab + 1; top_jtrange_tables= 1; table= &parent->table_reexec[0]; parent->table_reexec[0]= tmp_table; @@ -7701,21 +7699,8 @@ make_join_readinfo(JOIN *join, ulonglong options, uint no_jbuf_after) tab->sorted= sorted; sorted= 0; // only first must be sorted - - //if (sj_is_materialize_strategy(join->best_positions[i].sj_strategy)) - if (tab->bush_children) // SJM + if (tab->bush_children) { - /* This is a start of semi-join nest */ - //first_sjm_table= i; - //last_sjm_table= i + join->best_positions[i].n_sj_tables; - /* - psergey2: dont: - if (i == join->const_tables) - join->first_select= sub_select_sjm; - else - tab[-1].next_select= sub_select_sjm; - */ - if (setup_sj_materialization(tab)) return TRUE; table= tab->table; @@ -12717,9 +12702,9 @@ do_select(JOIN *join,List<Item> *fields,TABLE *table,Procedure *procedure) else { DBUG_ASSERT(join->tables); - error= join->first_select(join,join_tab,0); + error= sub_select(join,join_tab,0); if (error == NESTED_LOOP_OK || error == NESTED_LOOP_NO_MORE_ROWS) - error= join->first_select(join,join_tab,1); + error= sub_select(join,join_tab,1); if (error == NESTED_LOOP_QUERY_LIMIT) error= NESTED_LOOP_OK; /* select_limit used */ } diff --git a/sql/sql_select.h b/sql/sql_select.h index 8319969432c..1dba84f7822 100644 --- a/sql/sql_select.h +++ b/sql/sql_select.h @@ -190,8 +190,15 @@ typedef struct st_join_table { psergey2: for join tabs that are inside a bush: root of this bush. */ st_join_table *bush_root_tab; - bool last_leaf_in_bush; + /* TRUE <=> This join_tab is inside a join bush and is the last leaf tab here */ + bool last_leaf_in_bush; + + /* + ptr - this is a bush, and ptr points to description of child join_tab + range + NULL - this join tab has no bush children + */ JOIN_TAB_RANGE *bush_children; /* Special content for EXPLAIN 'Extra' column or NULL if none */ @@ -500,13 +507,13 @@ protected: context can be accessed. */ JOIN *join; -#if 0 - /* - Cardinality of the range of join tables whose fields can be put into the - cache. (A table from the range not necessarily contributes to the cache.) + /* + JOIN_TAB of the first table that can have it's fields in the join cache. + That is, tables in the [start_tab, tab) range can have their fields in the + join cache. + If a join tab in the range represents an SJM-nest, then all tables from the + nest can have their fields in the join cache, too. */ - uint tables; -#endif JOIN_TAB *start_tab; /* @@ -1505,7 +1512,6 @@ public: /* We also maintain a stack of join optimization states in * join->positions[] */ /******* Join optimization state members end *******/ - Next_select_func first_select; /* The cost of best complete join plan found so far during optimization, after optimization phase - cost of picked join order (not taking into @@ -1691,7 +1697,6 @@ public: rollup.state= ROLLUP::STATE_NONE; no_const_tables= FALSE; - first_select= sub_select; } int prepare(Item ***rref_pointer_array, TABLE_LIST *tables, uint wind_num, |