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MySQL 8.0.40
Source Code Documentation
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MySQL 8.0.40
Source Code Documentation
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Query execution. More...
#include "sql/sql_executor.h"#include <algorithm>#include <atomic>#include <cassert>#include <cmath>#include <cstddef>#include <iterator>#include <memory>#include <string>#include <type_traits>#include <utility>#include <vector>#include "field_types.h"#include "lex_string.h"#include "m_ctype.h"#include "mem_root_deque.h"#include "my_alloc.h"#include "my_base.h"#include "my_bitmap.h"#include "my_byteorder.h"#include "my_checksum.h"#include "my_dbug.h"#include "my_hash_combine.h"#include "my_loglevel.h"#include "my_sqlcommand.h"#include "my_sys.h"#include "my_table_map.h"#include "mysql/components/services/bits/psi_bits.h"#include "mysql/components/services/log_builtins.h"#include "mysqld_error.h"#include "prealloced_array.h"#include "sql-common/json_dom.h"#include "sql/current_thd.h"#include "sql/field.h"#include "sql/filesort.h"#include "sql/handler.h"#include "sql/item.h"#include "sql/item_cmpfunc.h"#include "sql/item_func.h"#include "sql/item_sum.h"#include "sql/iterators/sorting_iterator.h"#include "sql/iterators/timing_iterator.h"#include "sql/join_optimizer/access_path.h"#include "sql/join_optimizer/bit_utils.h"#include "sql/join_optimizer/cost_model.h"#include "sql/join_optimizer/join_optimizer.h"#include "sql/join_optimizer/materialize_path_parameters.h"#include "sql/join_optimizer/relational_expression.h"#include "sql/join_optimizer/walk_access_paths.h"#include "sql/join_type.h"#include "sql/key.h"#include "sql/mem_root_array.h"#include "sql/mysqld.h"#include "sql/nested_join.h"#include "sql/opt_costmodel.h"#include "sql/opt_explain_format.h"#include "sql/opt_trace.h"#include "sql/query_options.h"#include "sql/record_buffer.h"#include "sql/sort_param.h"#include "sql/sql_array.h"#include "sql/sql_base.h"#include "sql/sql_bitmap.h"#include "sql/sql_class.h"#include "sql/sql_const.h"#include "sql/sql_delete.h"#include "sql/sql_list.h"#include "sql/sql_optimizer.h"#include "sql/sql_resolver.h"#include "sql/sql_select.h"#include "sql/sql_tmp_table.h"#include "sql/sql_update.h"#include "sql/table.h"#include "sql/temp_table_param.h"#include "sql/visible_fields.h"#include "sql/window.h"#include "tables_contained_in.h"#include "template_utils.h"#include "thr_lock.h"Enumerations | |
| enum class | Substructure { Substructure::NONE , Substructure::OUTER_JOIN , Substructure::SEMIJOIN , Substructure::WEEDOUT } |
Functions | |
| static int | read_system (TABLE *table) |
| Read a constant table when there is at most one matching row, using a table scan. More... | |
| static bool | alloc_group_fields (JOIN *join, ORDER *group) |
| Get a list of buffers for saving last group. More... | |
| string | RefToString (const Index_lookup &ref, const KEY *key, bool include_nulls) |
| bool | has_rollup_result (Item *item) |
| Checks if an item has a ROLLUP NULL which needs to be written to temp table. More... | |
| bool | is_rollup_group_wrapper (const Item *item) |
| Item * | unwrap_rollup_group (Item *item) |
| bool | prepare_sum_aggregators (Item_sum **sum_funcs, bool need_distinct) |
| bool | setup_sum_funcs (THD *thd, Item_sum **func_ptr) |
Call setup() for all sum functions. More... | |
| void | init_tmptable_sum_functions (Item_sum **func_ptr) |
| void | update_tmptable_sum_func (Item_sum **func_ptr, TABLE *tmp_table) |
| Update record 0 in tmp_table from record 1. More... | |
| bool | copy_funcs (Temp_table_param *param, const THD *thd, Copy_func_type type) |
| Copy result of functions to record in tmp_table. More... | |
| static bool | update_const_equal_items (THD *thd, Item *cond, JOIN_TAB *tab) |
| Check appearance of new constant items in multiple equalities of a condition after reading a constant table. More... | |
| void | setup_tmptable_write_func (QEP_TAB *tab, Opt_trace_object *trace) |
| Setup write_func of QEP_tmp_table object. More... | |
| static size_t | record_prefix_size (const TABLE *table) |
| Find out how many bytes it takes to store the smallest prefix which covers all the columns that will be read from a table. More... | |
| bool | set_record_buffer (TABLE *table, double expected_rows_to_fetch) |
| Allocate a data buffer that the storage engine can use for fetching batches of records. More... | |
| bool | ExtractConditions (Item *condition, Mem_root_array< Item * > *condition_parts) |
| Split AND conditions into their constituent parts, recursively. More... | |
| static bool | ContainsAnyMRRPaths (AccessPath *path) |
| See if “path” has any MRR nodes; if so, we cannot optimize them away in PossiblyAttachFilter(), as the BKA iterator expects there to be a corresponding MRR iterator. More... | |
| Item * | CreateConjunction (List< Item > *items) |
| Create an AND conjunction of all given items. More... | |
| AccessPath * | PossiblyAttachFilter (AccessPath *path, const vector< Item * > &conditions, THD *thd, table_map *conditions_depend_on_outer_tables) |
| Return a new iterator that wraps "iterator" and that tests all of the given conditions (if any), ANDed together. More... | |
| AccessPath * | CreateNestedLoopAccessPath (THD *thd, AccessPath *outer, AccessPath *inner, JoinType join_type, bool pfs_batch_mode) |
| static AccessPath * | NewInvalidatorAccessPathForTable (THD *thd, AccessPath *path, QEP_TAB *qep_tab, plan_idx table_index_to_invalidate) |
| static table_map | ConvertQepTabMapToTableMap (JOIN *join, qep_tab_map tables) |
| AccessPath * | CreateBKAAccessPath (THD *thd, JOIN *join, AccessPath *outer_path, qep_tab_map left_tables, AccessPath *inner_path, qep_tab_map right_tables, TABLE *table, Table_ref *table_list, Index_lookup *ref, JoinType join_type) |
| static AccessPath * | PossiblyAttachFilter (AccessPath *path, const vector< PendingCondition > &conditions, THD *thd, table_map *conditions_depend_on_outer_tables) |
| static Item_func_trig_cond * | GetTriggerCondOrNull (Item *item) |
| void | ConvertItemsToCopy (const mem_root_deque< Item * > &items, Field **fields, Temp_table_param *param) |
| For historical reasons, derived table materialization and temporary table materialization didn't specify the fields to materialize in the same way. More... | |
| static bool | IsJoinCondition (const Item *item, const QEP_TAB *qep_tab) |
| static Item * | GetInnermostCondition (Item *item) |
| static bool | CheckIfFieldsAvailableForCond (Item *item, table_map build_tables, table_map probe_tables) |
| static void | AttachSemiJoinCondition (Item *join_cond, vector< PendingCondition > *join_conditions, QEP_TAB *current_table, qep_tab_map left_tables, plan_idx semi_join_table_idx) |
| void | SplitConditions (Item *condition, QEP_TAB *current_table, vector< Item * > *predicates_below_join, vector< PendingCondition > *predicates_above_join, vector< PendingCondition > *join_conditions, plan_idx semi_join_table_idx, qep_tab_map left_tables) |
| static void | MarkUnhandledDuplicates (SJ_TMP_TABLE *weedout, plan_idx weedout_start, plan_idx weedout_end, qep_tab_map *unhandled_duplicates) |
| For a given duplicate weedout operation, figure out which tables are supposed to be deduplicated by it, and add those to unhandled_duplicates. More... | |
| static AccessPath * | CreateWeedoutOrLimitAccessPath (THD *thd, AccessPath *path, SJ_TMP_TABLE *weedout_table) |
| static AccessPath * | NewWeedoutAccessPathForTables (THD *thd, const qep_tab_map tables_to_deduplicate, QEP_TAB *qep_tabs, uint primary_tables, AccessPath *path) |
| static Substructure | FindSubstructure (QEP_TAB *qep_tabs, const plan_idx first_idx, const plan_idx this_idx, const plan_idx last_idx, CallingContext calling_context, bool *add_limit_1, plan_idx *substructure_end, qep_tab_map *unhandled_duplicates) |
| Given a range of tables (where we assume that we've already handled first_idx..(this_idx-1) as inner joins), figure out whether this is a semijoin, an outer join or a weedout. More... | |
| static bool | IsTableScan (AccessPath *path) |
| AccessPath * | GetAccessPathForDerivedTable (THD *thd, QEP_TAB *qep_tab, AccessPath *table_path) |
| static void | RecalculateTablePathCost (AccessPath *path, const Query_block &outer_query_block) |
| Recalculate the cost of 'path'. More... | |
| AccessPath * | MoveCompositeIteratorsFromTablePath (AccessPath *path, const Query_block &outer_query_block) |
| For a MATERIALIZE access path, move any non-basic iterators (e.g. More... | |
| AccessPath * | GetAccessPathForDerivedTable (THD *thd, Table_ref *table_ref, TABLE *table, bool rematerialize, Mem_root_array< const AccessPath * > *invalidators, bool need_rowid, AccessPath *table_path) |
| AccessPath * | GetTableAccessPath (THD *thd, QEP_TAB *qep_tab, QEP_TAB *qep_tabs) |
| Get the RowIterator used for scanning the given table, with any required materialization operations done first. More... | |
| void | SetCostOnTableAccessPath (const Cost_model_server &cost_model, const POSITION *pos, bool is_after_filter, AccessPath *path) |
| void | SetCostOnNestedLoopAccessPath (const Cost_model_server &cost_model, const POSITION *pos_inner, AccessPath *path) |
| void | SetCostOnHashJoinAccessPath (const Cost_model_server &cost_model, const POSITION *pos_outer, AccessPath *path) |
| static bool | ConditionIsAlwaysTrue (Item *item) |
| static AccessPath * | CreateHashJoinAccessPath (THD *thd, QEP_TAB *qep_tab, AccessPath *build_path, qep_tab_map build_tables, AccessPath *probe_path, qep_tab_map probe_tables, JoinType join_type, vector< Item * > *join_conditions, table_map *conditions_depend_on_outer_tables) |
| static void | ExtractJoinConditions (const QEP_TAB *current_table, vector< Item * > *predicates, vector< Item * > *join_conditions) |
| static bool | UseHashJoin (QEP_TAB *qep_tab) |
| static bool | UseBKA (QEP_TAB *qep_tab) |
| static bool | QueryMixesOuterBKAAndBNL (JOIN *join) |
| static bool | InsideOuterOrAntiJoin (QEP_TAB *qep_tab) |
| void | PickOutConditionsForTableIndex (int table_idx, vector< PendingCondition > *from, vector< PendingCondition > *to) |
| void | PickOutConditionsForTableIndex (int table_idx, vector< PendingCondition > *from, vector< Item * > *to) |
| AccessPath * | FinishPendingOperations (THD *thd, AccessPath *path, QEP_TAB *remove_duplicates_loose_scan_qep_tab, const vector< PendingCondition > &pending_conditions, table_map *conditions_depend_on_outer_tables) |
| AccessPath * | ConnectJoins (plan_idx upper_first_idx, plan_idx first_idx, plan_idx last_idx, QEP_TAB *qep_tabs, THD *thd, CallingContext calling_context, vector< PendingCondition > *pending_conditions, vector< PendingInvalidator > *pending_invalidators, vector< PendingCondition > *pending_join_conditions, qep_tab_map *unhandled_duplicates, table_map *conditions_depend_on_outer_tables) |
| For a given slice of the table list, build up the iterator tree corresponding to the tables in that slice. More... | |
| static table_map | get_update_or_delete_target_tables (const JOIN *join) |
| int | do_sj_dups_weedout (THD *thd, SJ_TMP_TABLE *sjtbl) |
| SemiJoinDuplicateElimination: Weed out duplicate row combinations. More... | |
| int | report_handler_error (TABLE *table, int error) |
| Help function when we get some an error from the table handler. More... | |
| int | join_read_const_table (JOIN_TAB *tab, POSITION *pos) |
| Reads content of constant table. More... | |
| int | read_const (TABLE *table, Index_lookup *ref) |
| static bool | cmp_field_value (Field *field, ptrdiff_t diff) |
| static bool | group_rec_cmp (ORDER *group, uchar *rec0, uchar *rec1) |
| Compare GROUP BY in from tmp table's record[0] and record[1]. More... | |
| static bool | table_rec_cmp (TABLE *table) |
| Compare GROUP BY in from tmp table's record[0] and record[1]. More... | |
| ulonglong | unique_hash (const Field *field, ulonglong *hash_val) |
| Generate hash for a field. More... | |
| static ulonglong | unique_hash_group (ORDER *group) |
| Generate hash for unique constraint according to group-by list. More... | |
| static ulonglong | unique_hash_fields (TABLE *table) |
| Generate hash for unique_constraint for all visible fields of a table. More... | |
| bool | check_unique_constraint (TABLE *table) |
| Check unique_constraint. More... | |
| bool | construct_lookup (THD *thd, TABLE *table, Index_lookup *ref) |
| Copy the lookup key into the table ref's key buffer. More... | |
| bool | make_group_fields (JOIN *main_join, JOIN *curr_join) |
| allocate group fields or take prepared (cached). More... | |
| int | update_item_cache_if_changed (List< Cached_item > &list) |
| static size_t | compute_ria_idx (const mem_root_deque< Item * > &fields, size_t i, size_t added_non_hidden_fields, size_t border) |
| Compute the position mapping from fields to ref_item_array, cf. More... | |
| bool | copy_fields (Temp_table_param *param, const THD *thd, bool reverse_copy) |
| Make a copy of all simple SELECT'ed fields. More... | |
| static bool | replace_embedded_rollup_references_with_tmp_fields (THD *thd, Item *item, mem_root_deque< Item * > *fields) |
| For each rollup wrapper below the given item, replace it with a temporary field, e.g. More... | |
| bool | change_to_use_tmp_fields (mem_root_deque< Item * > *fields, THD *thd, Ref_item_array ref_item_array, mem_root_deque< Item * > *res_fields, size_t added_non_hidden_fields) |
| Change all funcs and sum_funcs to fields in tmp table, and create new list of all items. More... | |
| static Item_rollup_group_item * | find_rollup_item_in_group_list (Item *item, Query_block *query_block) |
| bool | replace_contents_of_rollup_wrappers_with_tmp_fields (THD *thd, Query_block *select, Item *item_arg) |
| For each rollup wrapper below the given item, replace its argument with a temporary field, e.g. More... | |
| bool | change_to_use_tmp_fields_except_sums (mem_root_deque< Item * > *fields, THD *thd, Query_block *select, Ref_item_array ref_item_array, mem_root_deque< Item * > *res_fields, size_t added_non_hidden_fields) |
| Change all sum_func refs to fields to point at fields in tmp table. More... | |
| bool | MaterializeIsDoingDeduplication (TABLE *table) |
| (end of group Query_Executor) More... | |
| AccessPath * | create_table_access_path (THD *thd, TABLE *table, AccessPath *range_scan, Table_ref *table_ref, POSITION *position, bool count_examined_rows) |
| create_table_access_path is used to scan by using a number of different methods. More... | |
| unique_ptr_destroy_only< RowIterator > | init_table_iterator (THD *thd, TABLE *table, AccessPath *range_scan, Table_ref *table_ref, POSITION *position, bool ignore_not_found_rows, bool count_examined_rows) |
| Creates an iterator for the given table, then calls Init() on the resulting iterator. More... | |
Variables | |
| static constexpr size_t | MIN_RECORD_BUFFER_SIZE = 4 * 1024 |
| The minimum size of the record buffer allocated by set_record_buffer(). More... | |
| static constexpr size_t | MAX_RECORD_BUFFER_SIZE = 128 * 1024 |
| The maximum size of the record buffer allocated by set_record_buffer(). More... | |
| static constexpr double | RECORD_BUFFER_FRACTION = 0.1f |
| How big a fraction of the estimated number of returned rows to make room for in the record buffer allocated by set_record_buffer(). More... | |
Query execution.
| AccessPath * create_table_access_path | ( | THD * | thd, |
| TABLE * | table, | ||
| AccessPath * | range_scan, | ||
| Table_ref * | table_ref, | ||
| POSITION * | position, | ||
| bool | count_examined_rows | ||
| ) |
create_table_access_path is used to scan by using a number of different methods.
Which method to use is set-up in this call so that you can create an iterator from the returned access path and fetch rows through said iterator afterwards.
| thd | Thread handle |
| table | Table the data [originally] comes from |
| range_scan | AccessPath to scan the table with, or nullptr |
| table_ref | Position for the table, must be non-nullptr for WITH RECURSIVE |
| position | Place to get cost information from, or nullptr |
| count_examined_rows | See AccessPath::count_examined_rows. |
| unique_ptr_destroy_only< RowIterator > init_table_iterator | ( | THD * | thd, |
| TABLE * | table, | ||
| AccessPath * | range_scan, | ||
| Table_ref * | table_ref, | ||
| POSITION * | position, | ||
| bool | ignore_not_found_rows, | ||
| bool | count_examined_rows | ||
| ) |
Creates an iterator for the given table, then calls Init() on the resulting iterator.
Unlike create_table_iterator(), this can create iterators for sort buffer results (which are set in the TABLE object during query execution). Returns nullptr on failure.
| bool MaterializeIsDoingDeduplication | ( | TABLE * | table | ) |
(end of group Query_Executor)
1.9.2