MDEV-12387 Push conditions into materialized subqueries

The logic and the implementation scheme are similar with the
MDEV-9197 Pushdown conditions into non-mergeable views/derived tables

How the push down is made on the example:

select * from t1
where a>3 and b>10 and
 (a,b) in (select x,max(y) from t2 group by x);

-->

select * from t1
where a>3 and b>10 and
  (a,b) in (select x,max(y)
            from t2
            where x>3
            group by x
            having max(y)>10);

The implementation scheme:

1. Search for the condition cond that depends only on the fields
   from the left part of the IN subquery (left_part)
2. Find fields F_group in the select of the right part of the
   IN subquery (right_part) that are used in the GROUP BY
3. Extract from the cond condition cond_where that depends only on the
   fields from the left_part that stay at the same places in the left_part
   (have the same indexes) as the F_group fields in the projection of the
   right_part
4. Transform cond_where so it can be pushed into the WHERE clause of the
   right_part and delete cond_where from the cond
5. Transform cond so it can be pushed into the HAVING clause of the right_part

The optimization is made in the
Item_in_subselect::pushdown_cond_for_in_subquery() and is controlled by the
variable condition_pushdown_for_subquery.

New test file in_subq_cond_pushdown.test is created.

There are also some changes made for setup_jtbm_semi_joins().
Now it is decomposed into the 2 procedures: setup_degenerate_jtbm_semi_joins()
that is called before optimize_cond() for cond and setup_jtbm_semi_joins()
that is called after optimize_cond().
New setup_jtbm_semi_joins() is made in the way so that the result of its work is
the same as if it was called before optimize_cond().

The code that is common for pushdown into materialized derived and into materialized
IN subqueries is factored out into pushdown_cond_for_derived(),
Item_in_subselect::pushdown_cond_for_in_subquery() and
st_select_lex::pushdown_cond_into_where_clause().

mysql-test/main/derived.result

@@ -632,7 +632,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 2	DERIVED	t1	system	NULL	NULL	NULL	NULL	1	100.00	
 Warnings:
 Note	1276	Field or reference 'sq.f2' of SELECT #3 was resolved in SELECT #1
-Note	1003	/* select#1 */ select 6 AS `f1` from  <materialize> (/* select#4 */ select `test`.`t2`.`f3` from `test`.`t2` having `test`.`t2`.`f3` >= 8) semi join (`test`.`t2`) where `test`.`t2`.`f3` = 6 and `<subquery4>`.`f3` = 9
+Note	1003	/* select#1 */ select 6 AS `f1` from  <materialize> (/* select#4 */ select `test`.`t2`.`f3` from `test`.`t2` having `test`.`t2`.`f3` >= 8) semi join (`test`.`t2`) where `<subquery4>`.`f3` = 9 and `test`.`t2`.`f3` = 6
 DROP TABLE t2,t1;
 #
 # MDEV-9462: Out of memory using explain on 2 empty tables 

mysql-test/main/mysqld--help.result

@@ -665,7 +665,8 @@ The following options may be given as the first argument:
  join_cache_hashed, join_cache_bka, 
  optimize_join_buffer_size, table_elimination, 
  extended_keys, exists_to_in, orderby_uses_equalities, 
- condition_pushdown_for_derived, split_materialized
+ condition_pushdown_for_derived, split_materialized, 
+ condition_pushdown_for_subquery
  --optimizer-use-condition-selectivity=# 
  Controls selectivity of which conditions the optimizer
  takes into account to calculate cardinality of a partial
@@ -1514,7 +1515,7 @@ old-style-user-limits FALSE
 optimizer-prune-level 1
 optimizer-search-depth 62
 optimizer-selectivity-sampling-limit 100
-optimizer-switch index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on
+optimizer-switch index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on,condition_pushdown_for_subquery=on
 optimizer-use-condition-selectivity 1
 performance-schema FALSE
 performance-schema-accounts-size -1

mysql-test/main/subselect_mat.result

@@ -1925,7 +1925,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where; Using join buffer (flat, BNL join)
 2	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	3	100.00	
 Warnings:
-Note	1003	/* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from  <materialize> (/* select#2 */ select max(`test`.`t2`.`c`) from `test`.`t2`) join `test`.`t1` where `test`.`t1`.`b` = 7 and `test`.`t1`.`a` = `<subquery2>`.`MAX(c)` and (<cache>(`<subquery2>`.`MAX(c)` is null) or `<subquery2>`.`MAX(c)` = 7)
+Note	1003	/* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from  <materialize> (/* select#2 */ select max(`test`.`t2`.`c`) from `test`.`t2` having `MAX(c)` is null or `MAX(c)` = 7) join `test`.`t1` where `test`.`t1`.`b` = 7 and `test`.`t1`.`a` = `<subquery2>`.`MAX(c)` and (<cache>(`<subquery2>`.`MAX(c)` is null) or `<subquery2>`.`MAX(c)` = 7)
 SELECT * FROM t1
 WHERE a IN (SELECT MAX(c) FROM t2) AND b=7 AND (a IS NULL OR a=b);
 a	b

mysql-test/main/subselect_sj_mat.result

@@ -1963,7 +1963,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where; Using join buffer (flat, BNL join)
 2	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	3	100.00	
 Warnings:
-Note	1003	/* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from  <materialize> (/* select#2 */ select max(`test`.`t2`.`c`) from `test`.`t2`) join `test`.`t1` where `test`.`t1`.`b` = 7 and `test`.`t1`.`a` = `<subquery2>`.`MAX(c)` and (<cache>(`<subquery2>`.`MAX(c)` is null) or `<subquery2>`.`MAX(c)` = 7)
+Note	1003	/* select#1 */ select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from  <materialize> (/* select#2 */ select max(`test`.`t2`.`c`) from `test`.`t2` having `MAX(c)` is null or `MAX(c)` = 7) join `test`.`t1` where `test`.`t1`.`b` = 7 and `test`.`t1`.`a` = `<subquery2>`.`MAX(c)` and (<cache>(`<subquery2>`.`MAX(c)` is null) or `<subquery2>`.`MAX(c)` = 7)
 SELECT * FROM t1
 WHERE a IN (SELECT MAX(c) FROM t2) AND b=7 AND (a IS NULL OR a=b);
 a	b

mysql-test/suite/sys_vars/r/sysvars_server_embedded.result

@@ -2673,17 +2673,17 @@ ENUM_VALUE_LIST	NULL
 READ_ONLY	NO
 COMMAND_LINE_ARGUMENT	REQUIRED
 VARIABLE_NAME	OPTIMIZER_SWITCH
-SESSION_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on
-GLOBAL_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on
+SESSION_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on,condition_pushdown_for_subquery=on
+GLOBAL_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on,condition_pushdown_for_subquery=on
 GLOBAL_VALUE_ORIGIN	COMPILE-TIME
-DEFAULT_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on
+DEFAULT_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on,condition_pushdown_for_subquery=on
 VARIABLE_SCOPE	SESSION
 VARIABLE_TYPE	FLAGSET
 VARIABLE_COMMENT	Fine-tune the optimizer behavior
 NUMERIC_MIN_VALUE	NULL
 NUMERIC_MAX_VALUE	NULL
 NUMERIC_BLOCK_SIZE	NULL
-ENUM_VALUE_LIST	index_merge,index_merge_union,index_merge_sort_union,index_merge_intersection,index_merge_sort_intersection,engine_condition_pushdown,index_condition_pushdown,derived_merge,derived_with_keys,firstmatch,loosescan,materialization,in_to_exists,semijoin,partial_match_rowid_merge,partial_match_table_scan,subquery_cache,mrr,mrr_cost_based,mrr_sort_keys,outer_join_with_cache,semijoin_with_cache,join_cache_incremental,join_cache_hashed,join_cache_bka,optimize_join_buffer_size,table_elimination,extended_keys,exists_to_in,orderby_uses_equalities,condition_pushdown_for_derived,split_materialized,default
+ENUM_VALUE_LIST	index_merge,index_merge_union,index_merge_sort_union,index_merge_intersection,index_merge_sort_intersection,engine_condition_pushdown,index_condition_pushdown,derived_merge,derived_with_keys,firstmatch,loosescan,materialization,in_to_exists,semijoin,partial_match_rowid_merge,partial_match_table_scan,subquery_cache,mrr,mrr_cost_based,mrr_sort_keys,outer_join_with_cache,semijoin_with_cache,join_cache_incremental,join_cache_hashed,join_cache_bka,optimize_join_buffer_size,table_elimination,extended_keys,exists_to_in,orderby_uses_equalities,condition_pushdown_for_derived,split_materialized,condition_pushdown_for_subquery,default
 READ_ONLY	NO
 COMMAND_LINE_ARGUMENT	REQUIRED
 VARIABLE_NAME	OPTIMIZER_USE_CONDITION_SELECTIVITY

mysql-test/suite/sys_vars/r/sysvars_server_notembedded.result

@@ -2883,17 +2883,17 @@ ENUM_VALUE_LIST	NULL
 READ_ONLY	NO
 COMMAND_LINE_ARGUMENT	REQUIRED
 VARIABLE_NAME	OPTIMIZER_SWITCH
-SESSION_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on
-GLOBAL_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on
+SESSION_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on,condition_pushdown_for_subquery=on
+GLOBAL_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on,condition_pushdown_for_subquery=on
 GLOBAL_VALUE_ORIGIN	COMPILE-TIME
-DEFAULT_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on
+DEFAULT_VALUE	index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on,condition_pushdown_for_subquery=on
 VARIABLE_SCOPE	SESSION
 VARIABLE_TYPE	FLAGSET
 VARIABLE_COMMENT	Fine-tune the optimizer behavior
 NUMERIC_MIN_VALUE	NULL
 NUMERIC_MAX_VALUE	NULL
 NUMERIC_BLOCK_SIZE	NULL
-ENUM_VALUE_LIST	index_merge,index_merge_union,index_merge_sort_union,index_merge_intersection,index_merge_sort_intersection,engine_condition_pushdown,index_condition_pushdown,derived_merge,derived_with_keys,firstmatch,loosescan,materialization,in_to_exists,semijoin,partial_match_rowid_merge,partial_match_table_scan,subquery_cache,mrr,mrr_cost_based,mrr_sort_keys,outer_join_with_cache,semijoin_with_cache,join_cache_incremental,join_cache_hashed,join_cache_bka,optimize_join_buffer_size,table_elimination,extended_keys,exists_to_in,orderby_uses_equalities,condition_pushdown_for_derived,split_materialized,default
+ENUM_VALUE_LIST	index_merge,index_merge_union,index_merge_sort_union,index_merge_intersection,index_merge_sort_intersection,engine_condition_pushdown,index_condition_pushdown,derived_merge,derived_with_keys,firstmatch,loosescan,materialization,in_to_exists,semijoin,partial_match_rowid_merge,partial_match_table_scan,subquery_cache,mrr,mrr_cost_based,mrr_sort_keys,outer_join_with_cache,semijoin_with_cache,join_cache_incremental,join_cache_hashed,join_cache_bka,optimize_join_buffer_size,table_elimination,extended_keys,exists_to_in,orderby_uses_equalities,condition_pushdown_for_derived,split_materialized,condition_pushdown_for_subquery,default
 READ_ONLY	NO
 COMMAND_LINE_ARGUMENT	REQUIRED
 VARIABLE_NAME	OPTIMIZER_USE_CONDITION_SELECTIVITY

sql/item.h

@@ -569,6 +569,7 @@ typedef bool (Item::*Item_processor) (void *arg);
 typedef bool (Item::*Item_analyzer) (uchar **argp);
 typedef Item* (Item::*Item_transformer) (THD *thd, uchar *arg);
 typedef void (*Cond_traverser) (const Item *item, void *arg);
+typedef bool (Item::*Pushdown_checker) (uchar *arg);
 
 struct st_cond_statistic;
 
@@ -601,6 +602,7 @@ class String_copier_for_item: public String_copier
   String_copier_for_item(THD *thd): m_thd(thd) { }
 };
 
+
 class Item: public Value_source,
             public Type_all_attributes
 {
@@ -1647,7 +1649,15 @@ class Item: public Value_source,
     or can be converted to such an exression using equalities.
     Not to be used for AND/OR formulas.
   */
-  virtual bool excl_dep_on_grouping_fields(st_select_lex *sel) { return false; }
+  virtual bool excl_dep_on_grouping_fields(st_select_lex *sel)
+  { return false; }
+  /*
+    TRUE if the expression depends only on fields from the left part of
+    IN subquery or can be converted to such an expression using equalities.
+    Not to be used for AND/OR formulas.
+  */
+  virtual bool excl_dep_on_in_subq_left_part(Item_in_subselect *subq_pred)
+  { return false; }
 
   virtual bool switch_to_nullable_fields_processor(void *arg) { return 0; }
   virtual bool find_function_processor (void *arg) { return 0; }
@@ -1825,8 +1835,12 @@ class Item: public Value_source,
   { return this; }
   virtual Item *derived_field_transformer_for_where(THD *thd, uchar *arg)
   { return this; }
-  virtual Item *derived_grouping_field_transformer_for_where(THD *thd,
-                                                             uchar *arg)
+  virtual Item *grouping_field_transformer_for_where(THD *thd, uchar *arg)
+  { return this; }
+  /* Now is not used. */
+  virtual Item *in_subq_field_transformer_for_where(THD *thd, uchar *arg)
+  { return this; }
+  virtual Item *in_subq_field_transformer_for_having(THD *thd, uchar *arg)
   { return this; }
   virtual Item *in_predicate_to_in_subs_transformer(THD *thd, uchar *arg)
   { return this; }
@@ -2023,6 +2037,33 @@ class Item: public Value_source,
   {
     marker &= ~EXTRACTION_MASK;
   }
+  void check_pushable_cond(Pushdown_checker excl_dep_func, uchar *arg);
+  bool pushable_cond_checker_for_derived(uchar *arg)
+  {
+    return excl_dep_on_table(*((table_map *)arg));
+  }
+  bool pushable_cond_checker_for_subquery(uchar *arg)
+  {
+    return excl_dep_on_in_subq_left_part((Item_in_subselect *)arg);
+  }
+  Item *get_corresponding_field_in_insubq(Item_in_subselect *subq_pred);
+  Item *build_pushable_cond(THD *thd,
+                            Pushdown_checker checker,
+                            uchar *arg);
+  /*
+    Checks if this item depends only on the arg table
+  */
+  bool pushable_equality_checker_for_derived(uchar *arg)
+  {
+    return (used_tables() == *((table_map *)arg));
+  }
+  /*
+    Checks if this item consists in the left part of arg IN subquery predicate
+  */
+  bool pushable_equality_checker_for_subquery(uchar *arg)
+  {
+    return get_corresponding_field_in_insubq((Item_in_subselect *)arg);
+  }
 };
 
 MEM_ROOT *get_thd_memroot(THD *thd);
@@ -2151,6 +2192,17 @@ class Item_args
     }
     return true;
   }
+  bool excl_dep_on_in_subq_left_part(Item_in_subselect *subq_pred)
+  {
+    for (uint i= 0; i < arg_count; i++)
+    {
+      if (args[i]->const_item())
+        continue;
+      if (!args[i]->excl_dep_on_in_subq_left_part(subq_pred))
+        return false;
+    }
+    return true;
+  }
 public:
   Item_args(void)
     :args(NULL), arg_count(0)
@@ -3046,10 +3098,13 @@ class Item_field :public Item_ident,
   virtual Item *update_value_transformer(THD *thd, uchar *select_arg);
   Item *derived_field_transformer_for_having(THD *thd, uchar *arg);
   Item *derived_field_transformer_for_where(THD *thd, uchar *arg);
-  Item *derived_grouping_field_transformer_for_where(THD *thd, uchar *arg);
+  Item *grouping_field_transformer_for_where(THD *thd, uchar *arg);
+  Item *in_subq_field_transformer_for_where(THD *thd, uchar *arg);
+  Item *in_subq_field_transformer_for_having(THD *thd, uchar *arg);
   virtual void print(String *str, enum_query_type query_type);
   bool excl_dep_on_table(table_map tab_map);
   bool excl_dep_on_grouping_fields(st_select_lex *sel);
+  bool excl_dep_on_in_subq_left_part(Item_in_subselect *subq_pred);
   bool cleanup_excluding_fields_processor(void *arg)
   { return field ? 0 : cleanup_processor(arg); }
   bool cleanup_excluding_const_fields_processor(void *arg)
@@ -4874,6 +4929,8 @@ class Item_ref :public Item_ident
   }
   bool excl_dep_on_grouping_fields(st_select_lex *sel)
   { return (*ref)->excl_dep_on_grouping_fields(sel); }
+  bool excl_dep_on_in_subq_left_part(Item_in_subselect *subq_pred)
+  { return (*ref)->excl_dep_on_in_subq_left_part(subq_pred); }
   bool cleanup_excluding_fields_processor(void *arg)
   {
     Item *item= real_item();
@@ -5188,10 +5245,12 @@ class Item_direct_view_ref :public Item_direct_ref
   }
   bool excl_dep_on_table(table_map tab_map);
   bool excl_dep_on_grouping_fields(st_select_lex *sel);
+  bool excl_dep_on_in_subq_left_part(Item_in_subselect *subq_pred);
   Item *derived_field_transformer_for_having(THD *thd, uchar *arg);
   Item *derived_field_transformer_for_where(THD *thd, uchar *arg);
-  Item *derived_grouping_field_transformer_for_where(THD *thd,
-                                                     uchar *arg);
+  Item *grouping_field_transformer_for_where(THD *thd, uchar *arg);
+  Item *in_subq_field_transformer_for_where(THD *thd, uchar *arg);
+  Item *in_subq_field_transformer_for_having(THD *thd, uchar *arg);
 
   void save_val(Field *to)
   {
@@ -6110,7 +6169,11 @@ class Item_cache: public Item_basic_constant,
   { return convert_to_basic_const_item(thd); }
   Item *derived_field_transformer_for_where(THD *thd, uchar *arg)
   { return convert_to_basic_const_item(thd); }
-  Item *derived_grouping_field_transformer_for_where(THD *thd, uchar *arg)
+  Item *grouping_field_transformer_for_where(THD *thd, uchar *arg)
+  { return convert_to_basic_const_item(thd); }
+  Item *in_subq_field_transformer_for_where(THD *thd, uchar *arg)
+  { return convert_to_basic_const_item(thd); }
+  Item *in_subq_field_transformer_for_having(THD *thd, uchar *arg)
   { return convert_to_basic_const_item(thd); }
 };
 

sql/item_cmpfunc.h

@@ -1272,7 +1272,11 @@ class Item_func_nullif :public Item_func_case_expression
   { reset_first_arg_if_needed(); return this; }
   Item *derived_field_transformer_for_where(THD *thd, uchar *arg)
   { reset_first_arg_if_needed(); return this; }
-  Item *derived_grouping_field_transformer_for_where(THD *thd, uchar *arg)
+  Item *grouping_field_transformer_for_where(THD *thd, uchar *arg)
+  { reset_first_arg_if_needed(); return this; }
+  Item *in_subq_field_transformer_for_where(THD *thd, uchar *arg)
+  { reset_first_arg_if_needed(); return this; }
+  Item *in_subq_field_transformer_for_having(THD *thd, uchar *arg)
   { reset_first_arg_if_needed(); return this; }
 };
 
@@ -3135,6 +3139,8 @@ class Item_equal: public Item_bool_func
   {
     return used_tables() & tab_map;
   }
+  bool excl_dep_on_in_subq_left_part(Item_in_subselect *subq_pred);
+
   friend class Item_equal_fields_iterator;
   bool count_sargable_conds(void *arg);
   friend class Item_equal_iterator<List_iterator_fast,Item>;

sql/item_func.h

@@ -326,6 +326,11 @@ class Item_func :public Item_func_or_sum
     return Item_args::excl_dep_on_grouping_fields(sel);
   }
 
+  bool excl_dep_on_in_subq_left_part(Item_in_subselect *subq_pred)
+  {
+    return Item_args::excl_dep_on_in_subq_left_part(subq_pred);
+  }
+
   /*
     We assume the result of any function that has a TIMESTAMP argument to be
     timezone-dependent, since a TIMESTAMP value in both numeric and string

sql/item_row.h

@@ -134,6 +134,11 @@ class Item_row: public Item,
     return Item_args::excl_dep_on_grouping_fields(sel);
   }
 
+  bool excl_dep_on_in_subq_left_part(Item_in_subselect *subq_pred)
+  {
+    return Item_args::excl_dep_on_in_subq_left_part(subq_pred);
+  }
+
   bool check_vcol_func_processor(void *arg) {return FALSE; }
   Item *get_copy(THD *thd)
   { return get_item_copy<Item_row>(thd, this); }

sql/item_subselect.h

@@ -33,6 +33,7 @@ class subselect_hash_sj_engine;
 class Item_bool_func2;
 class Comp_creator;
 class With_element;
+class Field_pair;
 
 typedef class st_select_lex SELECT_LEX;
 
@@ -570,6 +571,8 @@ class Item_in_subselect :public Item_exists_subselect
   */
   bool is_registered_semijoin;
   
+  List<Field_pair> corresponding_fields;
+
   /*
     Used to determine how this subselect item is represented in the item tree,
     in case there is a need to locate it there and replace with something else.
@@ -741,6 +744,8 @@ class Item_in_subselect :public Item_exists_subselect
     return 0;
   };
 
+  bool pushdown_cond_for_in_subquery(THD *thd, Item *cond);
+
   friend class Item_ref_null_helper;
   friend class Item_is_not_null_test;
   friend class Item_in_optimizer;
@@ -852,7 +857,6 @@ class subselect_engine: public Sql_alloc,
   void set_row(List<Item> &item_list, Item_cache **row);
 };
 
-
 class subselect_single_select_engine: public subselect_engine
 {
   bool prepared;       /* simple subselect is prepared */
@@ -886,9 +890,10 @@ class subselect_single_select_engine: public subselect_engine
 
   friend class subselect_hash_sj_engine;
   friend class Item_in_subselect;
-  friend bool setup_jtbm_semi_joins(JOIN *join, List<TABLE_LIST> *join_list,
-                                    Item **join_where);
-
+  friend bool execute_degenerate_jtbm_semi_join(THD *thd,
+                                                TABLE_LIST *tbl,
+                                                Item_in_subselect *subq_pred,
+                                                List<Item> &eq_list);
 };
 
 

sql/opt_subselect.h

@@ -26,8 +26,15 @@ int check_and_do_in_subquery_rewrites(JOIN *join);
 bool convert_join_subqueries_to_semijoins(JOIN *join);
 int pull_out_semijoin_tables(JOIN *join);
 bool optimize_semijoin_nests(JOIN *join, table_map all_table_map);
+Item *and_new_conditions_to_optimized_cond(THD *thd, Item *cond,
+                                           COND_EQUAL **cond_eq,
+                                           List<Item> &new_conds,
+                                           Item::cond_result *cond_value);
+bool setup_degenerate_jtbm_semi_joins(JOIN *join,
+                                      List<TABLE_LIST> *join_list,
+                                      List<Item> &eq_list);
 bool setup_jtbm_semi_joins(JOIN *join, List<TABLE_LIST> *join_list,
-                           Item **join_where);
+                           List<Item> &eq_list);
 void cleanup_empty_jtbm_semi_joins(JOIN *join, List<TABLE_LIST> *join_list);
 
 // used by Loose_scan_opt

sql/sql_priv.h

@@ -228,6 +228,7 @@
 #define OPTIMIZER_SWITCH_ORDERBY_EQ_PROP           (1ULL << 29)
 #define OPTIMIZER_SWITCH_COND_PUSHDOWN_FOR_DERIVED (1ULL << 30)
 #define OPTIMIZER_SWITCH_SPLIT_MATERIALIZED        (1ULL << 31)
+#define OPTIMIZER_SWITCH_COND_PUSHDOWN_FOR_SUBQUERY (1ULL << 32)
 
 #define OPTIMIZER_SWITCH_DEFAULT   (OPTIMIZER_SWITCH_INDEX_MERGE | \
                                     OPTIMIZER_SWITCH_INDEX_MERGE_UNION | \
@@ -254,7 +255,8 @@
                                     OPTIMIZER_SWITCH_EXISTS_TO_IN | \
                                     OPTIMIZER_SWITCH_ORDERBY_EQ_PROP | \
                                     OPTIMIZER_SWITCH_COND_PUSHDOWN_FOR_DERIVED | \
-                                    OPTIMIZER_SWITCH_SPLIT_MATERIALIZED)
+                                    OPTIMIZER_SWITCH_SPLIT_MATERIALIZED | \
+                                    OPTIMIZER_SWITCH_COND_PUSHDOWN_FOR_SUBQUERY)
 
 /*
   Replication uses 8 bytes to store SQL_MODE in the binary log. The day you

sql/sys_vars.cc

@@ -2472,6 +2472,7 @@ export const char *optimizer_switch_names[]=
   "orderby_uses_equalities",
   "condition_pushdown_for_derived",
   "split_materialized",
+  "condition_pushdown_for_subquery",
   "default", 
   NullS
 };