MySQL 8.4.3
Source Code Documentation
sql_select.cc File Reference

Evaluate query expressions, throughout resolving, optimization and execution. More...

#include "sql/sql_select.h"
#include <stdio.h>
#include <string.h>
#include <algorithm>
#include <atomic>
#include <cstdio>
#include <cstring>
#include <initializer_list>
#include <memory>
#include <string>
#include <string_view>
#include "field_types.h"
#include "lex_string.h"
#include "m_string.h"
#include "mem_root_deque.h"
#include "my_alloc.h"
#include "my_bitmap.h"
#include "my_byteorder.h"
#include "my_compiler.h"
#include "my_dbug.h"
#include "my_pointer_arithmetic.h"
#include "my_sqlcommand.h"
#include "my_sys.h"
#include "mysql/plugin.h"
#include "mysql/strings/m_ctype.h"
#include "mysql/udf_registration_types.h"
#include "mysql_com.h"
#include "mysqld_error.h"
#include "scope_guard.h"
#include "sql-common/json_dom.h"
#include "sql-common/my_decimal.h"
#include "sql/auth/auth_acls.h"
#include "sql/auth/auth_common.h"
#include "sql/auth/sql_security_ctx.h"
#include "sql/current_thd.h"
#include "sql/debug_sync.h"
#include "sql/enum_query_type.h"
#include "sql/error_handler.h"
#include "sql/field.h"
#include "sql/filesort.h"
#include "sql/handler.h"
#include "sql/intrusive_list_iterator.h"
#include "sql/item.h"
#include "sql/item_func.h"
#include "sql/item_json_func.h"
#include "sql/item_subselect.h"
#include "sql/item_sum.h"
#include "sql/iterators/row_iterator.h"
#include "sql/iterators/sorting_iterator.h"
#include "sql/join_optimizer/access_path.h"
#include "sql/join_optimizer/bit_utils.h"
#include "sql/join_optimizer/join_optimizer.h"
#include "sql/join_optimizer/replace_item.h"
#include "sql/key.h"
#include "sql/key_spec.h"
#include "sql/lock.h"
#include "sql/mysqld.h"
#include "sql/nested_join.h"
#include "sql/opt_explain.h"
#include "sql/opt_explain_format.h"
#include "sql/opt_hints.h"
#include "sql/opt_trace.h"
#include "sql/opt_trace_context.h"
#include "sql/parse_tree_node_base.h"
#include "sql/query_options.h"
#include "sql/query_result.h"
#include "sql/range_optimizer/path_helpers.h"
#include "sql/range_optimizer/range_optimizer.h"
#include "sql/set_var.h"
#include "sql/sql_base.h"
#include "sql/sql_class.h"
#include "sql/sql_cmd.h"
#include "sql/sql_do.h"
#include "sql/sql_error.h"
#include "sql/sql_executor.h"
#include "sql/sql_insert.h"
#include "sql/sql_join_buffer.h"
#include "sql/sql_lex.h"
#include "sql/sql_list.h"
#include "sql/sql_optimizer.h"
#include "sql/sql_parse.h"
#include "sql/sql_planner.h"
#include "sql/sql_plugin.h"
#include "sql/sql_resolver.h"
#include "sql/sql_test.h"
#include "sql/sql_timer.h"
#include "sql/sql_tmp_table.h"
#include "sql/system_variables.h"
#include "sql/table.h"
#include "sql/temp_table_param.h"
#include "sql/thd_raii.h"
#include "sql/window.h"
#include "sql_string.h"
#include "template_utils.h"
#include "thr_lock.h"

Classes

class  anonymous_namespace{sql_select.cc}::store_key_const_item
 
class  anonymous_namespace{sql_select.cc}::store_key_json_item
 

Namespaces

namespace  anonymous_namespace{sql_select.cc}
 

Typedefs

using Global_tables_iterator = IntrusiveListIterator< Table_ref, &Table_ref::next_global >
 
using Global_tables_list = IteratorContainer< Global_tables_iterator >
 A list interface over the Table_ref::next_global pointer. More...
 

Functions

static store_keyget_store_key (THD *thd, Item *val, table_map used_tables, table_map const_tables, const KEY_PART_INFO *key_part, uchar *key_buff, uint maybe_null)
 
static bool retry_with_secondary_engine (THD *thd)
 Checks if a query should be retried using a secondary storage engine. More...
 
bool is_show_cmd_using_system_view (THD *thd)
 Check whether the statement is a SHOW command using INFORMATION_SCHEMA system views. More...
 
static ulong get_max_execution_time (THD *thd)
 Get the maximum execution time for a statement. More...
 
static bool is_timer_applicable_to_statement (THD *thd)
 Check whether max statement time is applicable to statement or not. More...
 
bool set_statement_timer (THD *thd)
 Set the time until the currently running statement is aborted. More...
 
void reset_statement_timer (THD *thd)
 Deactivate the timer associated with the statement that was executed. More...
 
bool reads_not_secondary_columns (const LEX *lex)
 Checks if a query reads a column that is not available in the secondary engine (i.e. More...
 
static bool has_secondary_engine_defined (const LEX *lex)
 
static bool equal_engines (const LEX_CSTRING &engine1, const LEX_CSTRING &engine2)
 
const MYSQL_LEX_CSTRINGget_eligible_secondary_engine_from (const LEX *lex)
 
const handlertonget_secondary_engine_handlerton (const LEX *lex)
 Returns secondary_engine handler for the statement. More...
 
std::string_view get_secondary_engine_fail_reason (const LEX *lex)
 
std::string_view find_secondary_engine_fail_reason (const LEX *lex)
 
static bool set_secondary_engine_fail_reason (const LEX *lex, std::string_view reason)
 
void set_fail_reason_and_raise_error (const LEX *lex, std::string_view reason)
 
void find_and_set_offload_fail_reason (const LEX *lex)
 
bool validate_use_secondary_engine (const LEX *lex)
 Validates a query that uses the secondary engine. More...
 
bool has_external_table (const LEX *lex)
 Checks if any of the tables referenced belong to an external engine. More...
 
void accumulate_statement_cost (const LEX *lex)
 Calculates the cost of executing a statement, including all its subqueries and stores it in thd->m_current_query_cost. More...
 
bool anonymous_namespace{sql_select.cc}::SecondaryEngineCallPrePrepareHook (THD *thd, const LEX_CSTRING &secondary_engine)
 Gets the secondary storage engine pre prepare hook function, if any. More...
 
bool optimize_secondary_engine (THD *thd)
 Perform query optimizations that are specific to a secondary storage engine. More...
 
void notify_plugins_after_select (THD *thd, const Sql_cmd *cmd)
 Notify plugins about an executed SELECT statement. More...
 
static bool check_locking_clause_access (THD *thd, Global_tables_list tables)
 Performs access check for the locking clause, if present. More...
 
bool types_allow_materialization (Item *outer, Item *inner)
 Check if two items are compatible wrt. More...
 
static bool sj_table_is_included (JOIN *join, JOIN_TAB *join_tab)
 
SJ_TMP_TABLEcreate_sj_tmp_table (THD *thd, JOIN *join, SJ_TMP_TABLE_TAB *first_tab, SJ_TMP_TABLE_TAB *last_tab)
 Set up the support structures (NULL bits, row offsets, etc.) for a semijoin duplicate weedout table. More...
 
static bool setup_semijoin_dups_elimination (JOIN *join, uint no_jbuf_after)
 Setup the strategies to eliminate semi-join duplicates. More...
 
static void destroy_sj_tmp_tables (JOIN *join)
 
bool check_privileges_for_join (THD *thd, mem_root_deque< Table_ref * > *tables)
 Check privileges for column references in a JOIN expression. More...
 
bool check_privileges_for_list (THD *thd, const mem_root_deque< Item * > &items, Access_bitmask privileges)
 Check privileges for column references in an item list. More...
 
void calc_used_field_length (TABLE *table, bool needs_rowid, uint *p_used_fieldlength)
 Find how much space the previous read not const tables takes in cache. More...
 
void calc_length_and_keyparts (Key_use *keyuse, JOIN_TAB *tab, const uint key, table_map used_tables, Key_use **chosen_keyuses, uint *length_out, uint *keyparts_out, table_map *dep_map, bool *maybe_null)
 Calculate properties of ref key: key length, number of used key parts, dependency map, possibility of null. More...
 
bool init_ref (THD *thd, unsigned keyparts, unsigned length, unsigned keyno, Index_lookup *ref)
 Initialize the given TABLE_REF; setting basic fields and allocating memory for arrays. More...
 
bool init_ref_part (THD *thd, unsigned part_no, Item *val, bool *cond_guard, bool null_rejecting, table_map const_tables, table_map used_tables, bool nullable, const KEY_PART_INFO *key_part_info, uchar *key_buff, Index_lookup *ref)
 Initialize a given keypart in the table ref. More...
 
bool create_ref_for_key (JOIN *join, JOIN_TAB *j, Key_use *org_keyuse, table_map used_tables)
 Setup a ref access for looking up rows via an index (a key). More...
 
static store_key::store_key_result type_conversion_status_to_store_key (THD *thd, type_conversion_status ts)
 
bool and_conditions (Item **e1, Item *e2)
 Extend e1 by AND'ing e2 to the condition e1 points to. More...
 
static Itemmake_cond_for_index (Item *cond, TABLE *table, uint keyno, bool other_tbls_ok)
 
static Itemmake_cond_remainder (Item *cond, bool exclude_index)
 
bool make_join_readinfo (JOIN *join, uint no_jbuf_after)
 Plan refinement stage: do various setup things for the executor. More...
 
static void cleanup_table (TABLE *table)
 
ORDERsimple_remove_const (ORDER *order, Item *where)
 Filter out ORDER BY items that are equal to constants in WHERE condition. More...
 
bool equality_determines_uniqueness (const Item_func_comparison *func, const Item *v, const Item *c)
 Check if equality can be used to remove sub-clause of GROUP BY/ORDER BY. More...
 
bool equality_has_no_implicit_casts (const Item_func_comparison *func, const Item *item1, const Item *item2)
 Check whether equality between two items is exact, ie., there are no implicit casts involved. More...
 
static bool equal (const Item *i1, const Item *i2, const Field *f2)
 
bool check_field_is_const (Item *cond, const Item *order_item, const Field *order_field, Item **const_item)
 Check if a field is equal to a constant value in a condition. More...
 
void count_field_types (const Query_block *query_block, Temp_table_param *param, const mem_root_deque< Item * > &fields, bool reset_with_sum_func, bool save_sum_fields)
 Update TMP_TABLE_PARAM with count of the different type of fields. More...
 
bool test_if_subpart (ORDER *a, ORDER *b)
 Return 1 if second is a subpart of first argument. More...
 
void calc_group_buffer (JOIN *join, ORDER *group)
 calc how big buffer we need for comparing group entries. More...
 
void free_underlaid_joins (Query_block *select)
 Free joins of subselect of this select. More...
 
bool CreateFramebufferTable (THD *thd, const Temp_table_param &tmp_table_param, const Query_block &query_block, const mem_root_deque< Item * > &source_fields, const mem_root_deque< Item * > &window_output_fields, Func_ptr_array *mapping_from_source_to_window_output, Window *window)
 
bool test_if_cheaper_ordering (const JOIN_TAB *tab, ORDER_with_src *order, TABLE *table, Key_map usable_keys, int ref_key, ha_rows select_limit, int *new_key, int *new_key_direction, ha_rows *new_select_limit, uint *new_used_key_parts, uint *saved_best_key_parts, double *new_read_time)
 Find a cheaper access key than a given key. More...
 
uint get_index_for_order (ORDER_with_src *order, TABLE *table, ha_rows limit, AccessPath *range_scan, bool *need_sort, bool *reverse)
 Find a key to apply single table UPDATE/DELETE by a given ORDER. More...
 
uint actual_key_parts (const KEY *key_info)
 Returns number of key parts depending on OPTIMIZER_SWITCH_USE_INDEX_EXTENSIONS flag. More...
 
uint actual_key_flags (const KEY *key_info)
 Returns key flags depending on OPTIMIZER_SWITCH_USE_INDEX_EXTENSIONS flag. More...
 
join_type calc_join_type (AccessPath *path)
 

Detailed Description

Evaluate query expressions, throughout resolving, optimization and execution.