diff options
Diffstat (limited to 'sql/sql_select.cc')
| -rw-r--r-- | sql/sql_select.cc | 143 |
1 files changed, 94 insertions, 49 deletions
diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 660318b6044..c18f6edb23a 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -49,15 +49,15 @@ static int sort_keyuse(KEYUSE *a,KEYUSE *b); static void set_position(JOIN *join,uint index,JOIN_TAB *table,KEYUSE *key); static bool create_ref_for_key(JOIN *join, JOIN_TAB *j, KEYUSE *org_keyuse, table_map used_tables); -static void choose_plan(JOIN *join,table_map join_tables); +static bool choose_plan(JOIN *join,table_map join_tables); static void best_access_path(JOIN *join, JOIN_TAB *s, THD *thd, table_map remaining_tables, uint idx, double record_count, double read_time); static void optimize_straight_join(JOIN *join, table_map join_tables); -static void greedy_search(JOIN *join, table_map remaining_tables, +static bool greedy_search(JOIN *join, table_map remaining_tables, uint depth, uint prune_level); -static void best_extension_by_limited_search(JOIN *join, +static bool best_extension_by_limited_search(JOIN *join, table_map remaining_tables, uint idx, double record_count, double read_time, uint depth, @@ -69,7 +69,7 @@ static int join_tab_cmp_straight(const void* ptr1, const void* ptr2); TODO: 'find_best' is here only temporarily until 'greedy_search' is tested and approved. */ -static void find_best(JOIN *join,table_map rest_tables,uint index, +static bool find_best(JOIN *join,table_map rest_tables,uint index, double record_count,double read_time); static uint cache_record_length(JOIN *join,uint index); static double prev_record_reads(JOIN *join, uint idx, table_map found_ref); @@ -2755,7 +2755,8 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables, COND *conds, if (join->const_tables != join->tables) { optimize_keyuse(join, keyuse_array); - choose_plan(join, all_table_map & ~join->const_table_map); + if (choose_plan(join, all_table_map & ~join->const_table_map)) + DBUG_RETURN(TRUE); } else { @@ -4404,11 +4405,12 @@ best_access_path(JOIN *join, the array 'join->best_positions', and the cost of the plan in 'join->best_read'. - RETURN - None + RETURN VALUES + FALSE ok + TRUE Fatal error */ -static void +static bool choose_plan(JOIN *join, table_map join_tables) { uint search_depth= join->thd->variables.optimizer_search_depth; @@ -4441,14 +4443,16 @@ choose_plan(JOIN *join, table_map join_tables) the greedy version. Will be removed when greedy_search is approved. */ join->best_read= DBL_MAX; - find_best(join, join_tables, join->const_tables, 1.0, 0.0); + if (find_best(join, join_tables, join->const_tables, 1.0, 0.0)) + DBUG_RETURN(TRUE); } else { if (search_depth == 0) /* Automatically determine a reasonable value for 'search_depth' */ search_depth= determine_search_depth(join); - greedy_search(join, join_tables, search_depth, prune_level); + if (greedy_search(join, join_tables, search_depth, prune_level)) + DBUG_RETURN(TRUE); } } @@ -4456,7 +4460,7 @@ choose_plan(JOIN *join, table_map join_tables) Store the cost of this query into a user variable */ join->thd->status_var.last_query_cost= join->best_read; - DBUG_VOID_RETURN; + DBUG_RETURN(FALSE); } @@ -4684,11 +4688,12 @@ optimize_straight_join(JOIN *join, table_map join_tables) In the future, 'greedy_search' might be extended to support other implementations of 'best_extension', e.g. some simpler quadratic procedure. - RETURN - None + RETURN VALUES + FALSE ok + TRUE Fatal error */ -static void +static bool greedy_search(JOIN *join, table_map remaining_tables, uint search_depth, @@ -4710,8 +4715,9 @@ greedy_search(JOIN *join, do { /* Find the extension of the current QEP with the lowest cost */ join->best_read= DBL_MAX; - best_extension_by_limited_search(join, remaining_tables, idx, record_count, - read_time, search_depth, prune_level); + if (best_extension_by_limited_search(join, remaining_tables, idx, record_count, + read_time, search_depth, prune_level)) + DBUG_RETURN(TRUE); if (size_remain <= search_depth) { @@ -4722,7 +4728,7 @@ greedy_search(JOIN *join, DBUG_EXECUTE("opt", print_plan(join, join->tables, record_count, read_time, read_time, "optimal");); - DBUG_VOID_RETURN; + DBUG_RETURN(FALSE); } /* select the first table in the optimal extension as most promising */ @@ -4867,11 +4873,12 @@ greedy_search(JOIN *join, The parameter 'search_depth' provides control over the recursion depth, and thus the size of the resulting optimal plan. - RETURN - None + RETURN VALUES + FALSE ok + TRUE Fatal error */ -static void +static bool best_extension_by_limited_search(JOIN *join, table_map remaining_tables, uint idx, @@ -4880,11 +4887,12 @@ best_extension_by_limited_search(JOIN *join, uint search_depth, uint prune_level) { + DBUG_ENTER("best_extension_by_limited_search"); + THD *thd= join->thd; if (thd->killed) // Abort - return; + DBUG_RETURN(TRUE); - DBUG_ENTER("best_extension_by_limited_search"); DBUG_EXECUTE("opt", print_plan(join, idx, read_time, record_count, idx, "SOFAR:");); @@ -4966,15 +4974,14 @@ best_extension_by_limited_search(JOIN *join, if ( (search_depth > 1) && (remaining_tables & ~real_table_bit) ) { /* Recursively expand the current partial plan */ swap_variables(JOIN_TAB*, join->best_ref[idx], *pos); - best_extension_by_limited_search(join, - remaining_tables & ~real_table_bit, - idx + 1, - current_record_count, - current_read_time, - search_depth - 1, - prune_level); - if (thd->killed) - DBUG_VOID_RETURN; + if (best_extension_by_limited_search(join, + remaining_tables & ~real_table_bit, + idx + 1, + current_record_count, + current_read_time, + search_depth - 1, + prune_level)) + DBUG_RETURN(TRUE); swap_variables(JOIN_TAB*, join->best_ref[idx], *pos); } else @@ -5003,19 +5010,26 @@ best_extension_by_limited_search(JOIN *join, restore_prev_nj_state(s); } } - DBUG_VOID_RETURN; + DBUG_RETURN(FALSE); } /* TODO: this function is here only temporarily until 'greedy_search' is tested and accepted. + + RETURN VALUES + FALSE ok + TRUE Fatal error */ -static void +static bool find_best(JOIN *join,table_map rest_tables,uint idx,double record_count, double read_time) { + DBUG_ENTER("find_best"); THD *thd= join->thd; + if (thd->killed) + DBUG_RETURN(TRUE); if (!rest_tables) { DBUG_PRINT("best",("read_time: %g record_count: %g",read_time, @@ -5032,10 +5046,10 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count, sizeof(POSITION)*idx); join->best_read= read_time - 0.001; } - return; + DBUG_RETURN(FALSE); } if (read_time+record_count/(double) TIME_FOR_COMPARE >= join->best_read) - return; /* Found better before */ + DBUG_RETURN(FALSE); /* Found better before */ JOIN_TAB *s; double best_record_count=DBL_MAX,best_read_time=DBL_MAX; @@ -5068,10 +5082,9 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count, best_read_time=current_read_time; } swap_variables(JOIN_TAB*, join->best_ref[idx], *pos); - find_best(join,rest_tables & ~real_table_bit,idx+1, - current_record_count,current_read_time); - if (thd->killed) - return; + if (find_best(join,rest_tables & ~real_table_bit,idx+1, + current_record_count,current_read_time)) + DBUG_RETURN(TRUE); swap_variables(JOIN_TAB*, join->best_ref[idx], *pos); } restore_prev_nj_state(s); @@ -5079,6 +5092,7 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count, break; // Don't test all combinations } } + DBUG_RETURN(FALSE); } @@ -6099,13 +6113,39 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond) } /* - Push down all predicates from on expressions. - Each of these predicated are guarded by a variable + Push down conditions from all on expressions. + Each of these conditions are guarded by a variable that turns if off just before null complemented row for - outer joins is formed. Thus, the predicates from an + outer joins is formed. Thus, the condition from an 'on expression' are guaranteed not to be checked for the null complemented row. */ + + /* First push down constant conditions from on expressions */ + for (JOIN_TAB *join_tab= join->join_tab+join->const_tables; + join_tab < join->join_tab+join->tables ; join_tab++) + { + if (*join_tab->on_expr_ref) + { + JOIN_TAB *cond_tab= join_tab->first_inner; + COND *tmp= make_cond_for_table(*join_tab->on_expr_ref, + join->const_table_map, + (table_map) 0); + if (!tmp) + continue; + tmp= new Item_func_trig_cond(tmp, &cond_tab->not_null_compl); + if (!tmp) + DBUG_RETURN(1); + tmp->quick_fix_field(); + cond_tab->select_cond= !cond_tab->select_cond ? tmp : + new Item_cond_and(cond_tab->select_cond,tmp); + if (!cond_tab->select_cond) + DBUG_RETURN(1); + cond_tab->select_cond->quick_fix_field(); + } + } + + /* Push down non-constant conditions from on expressions */ JOIN_TAB *last_tab= tab; while (first_inner_tab && first_inner_tab->last_inner == last_tab) { @@ -6558,7 +6598,6 @@ void JOIN::cleanup(bool full) for (tab= join_tab, end= tab+tables; tab != end; tab++) tab->cleanup(); table= 0; - tables= 0; } else { @@ -8997,7 +9036,7 @@ Field *create_tmp_field_from_field(THD *thd, Field *org_field, Make sure that the blob fits into a Field_varstring which has 2-byte lenght. */ - if (convert_blob_length && convert_blob_length < UINT_MAX16 && + if (convert_blob_length && convert_blob_length <= Field_varstring::MAX_SIZE && (org_field->flags & BLOB_FLAG)) new_field= new Field_varstring(convert_blob_length, org_field->maybe_null(), @@ -9065,8 +9104,13 @@ static Field *create_tmp_field_from_item(THD *thd, Item *item, TABLE *table, item->name, item->decimals, TRUE); break; case INT_RESULT: - /* Select an integer type with the minimal fit precision */ - if (item->max_length > MY_INT32_NUM_DECIMAL_DIGITS) + /* + Select an integer type with the minimal fit precision. + MY_INT32_NUM_DECIMAL_DIGITS is sign inclusive, don't consider the sign. + Values with MY_INT32_NUM_DECIMAL_DIGITS digits may or may not fit into + Field_long : make them Field_longlong. + */ + if (item->max_length >= (MY_INT32_NUM_DECIMAL_DIGITS - 1)) new_field=new Field_longlong(item->max_length, maybe_null, item->name, item->unsigned_flag); else @@ -9090,7 +9134,8 @@ static Field *create_tmp_field_from_item(THD *thd, Item *item, TABLE *table, 2-byte lenght. */ else if (item->max_length/item->collation.collation->mbmaxlen > 255 && - convert_blob_length < UINT_MAX16 && convert_blob_length) + convert_blob_length <= Field_varstring::MAX_SIZE && + convert_blob_length) new_field= new Field_varstring(convert_blob_length, maybe_null, item->name, table->s, item->collation.collation); @@ -15537,8 +15582,8 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order, break; } } - if (tab->next_select == sub_select_cache) - extra.append(STRING_WITH_LEN("; Using join cache")); + if (i > 0 && tab[-1].next_select == sub_select_cache) + extra.append(STRING_WITH_LEN("; Using join buffer")); /* Skip initial "; "*/ const char *str= extra.ptr(); |