Bug#37560280 Incorrect behavior with EXPLAIN and subqueries

EXPLAIN could execute a stored function in a subquery when the subquery
created a derived table, e.g.:
  EXPLAIN SELECT * FROM (SELECT f()) AS a;

This issue was caused by Table_ref::materializable_is_const(), which
incorrectly treated a function call as a constant expression.
Now, we ensure that a derived table subquery containing a stored
function call is not considered constant.

Change-Id: Id73d567b3617da1523996e8ee0ed73b4879451ad
(cherry picked from commit 2830b52f5515af4f7e9330492593446b215b004a)

Author: Volodymyr Verovkin

mysql-test/r/partition_locking.result

@@ -5030,9 +5030,9 @@ Handler_read_next	12
 UNLOCK TABLES;
 EXPLAIN SELECT * FROM t2 WHERE a = sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t2	p1	const	PRIMARY	PRIMARY	4	const	#	100.00	NULL
+1	SIMPLE	t2	p0,p1,p2	eq_ref	PRIMARY	PRIMARY	4	const	#	100.00	Using where
 Warnings:
-Note	1003	/* select#1 */ select '1' AS `a`,'1' AS `b` from `test`.`t2` where true
+Note	1003	/* select#1 */ select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t2` where (`test`.`t2`.`a` = <cache>(`sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
 START TRANSACTION;
 SELECT * FROM t2 WHERE a = sf_a_from_t1b_d('1');
@@ -5086,9 +5086,9 @@ Handler_read_next	12
 UNLOCK TABLES;
 EXPLAIN SELECT * FROM t2 WHERE a = 7 + sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t2	p2	const	PRIMARY	PRIMARY	4	const	#	100.00	NULL
+1	SIMPLE	t2	p0,p1,p2	eq_ref	PRIMARY	PRIMARY	4	const	#	100.00	Using where
 Warnings:
-Note	1003	/* select#1 */ select '8' AS `a`,'8' AS `b` from `test`.`t2` where true
+Note	1003	/* select#1 */ select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t2` where (`test`.`t2`.`a` = <cache>((7 + `sf_a_from_t1b_d`('1'))))
 FLUSH STATUS;
 START TRANSACTION;
 SELECT * FROM t2 WHERE a = 7 + sf_a_from_t1b_d('1');
@@ -5138,9 +5138,9 @@ Handler_read_next	7
 UNLOCK TABLES;
 EXPLAIN SELECT * FROM t2 WHERE a = sf_a_from_t1b_d('1') AND a = 2;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	#	NULL	Impossible WHERE
+1	SIMPLE	t2	p2	const	PRIMARY	PRIMARY	4	const	#	100.00	NULL
 Warnings:
-Note	1003	/* select#1 */ select `test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t2` where false
+Note	1003	/* select#1 */ select '2' AS `a`,'2' AS `b` from `test`.`t2` where ((2 = `sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
 START TRANSACTION;
 SELECT * FROM t2 WHERE a = sf_a_from_t1b_d('1') AND a = 2;
@@ -5322,9 +5322,9 @@ Handler_read_next	12
 UNLOCK TABLES;
 EXPLAIN SELECT sf_add_1(a) - 1, sf_add_hello(b) FROM t2 WHERE a = sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t2	p1	const	PRIMARY	PRIMARY	4	const	#	100.00	NULL
+1	SIMPLE	t2	p0,p1,p2	eq_ref	PRIMARY	PRIMARY	4	const	#	100.00	Using where
 Warnings:
-Note	1003	/* select#1 */ select (`sf_add_1`('1') - 1) AS `sf_add_1(a) - 1`,`sf_add_hello`('1') AS `sf_add_hello(b)` from `test`.`t2` where true
+Note	1003	/* select#1 */ select (`sf_add_1`(`test`.`t2`.`a`) - 1) AS `sf_add_1(a) - 1`,`sf_add_hello`(`test`.`t2`.`b`) AS `sf_add_hello(b)` from `test`.`t2` where (`test`.`t2`.`a` = <cache>(`sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
 START TRANSACTION;
 SELECT sf_add_1(a) - 1, sf_add_hello(b) FROM t2 WHERE a = sf_a_from_t1b_d('1');
@@ -5378,9 +5378,9 @@ Handler_read_next	12
 UNLOCK TABLES;
 EXPLAIN SELECT sf_add_1(a) - 1, sf_add_hello(b) FROM t2 WHERE a = 7 + sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t2	p2	const	PRIMARY	PRIMARY	4	const	#	100.00	NULL
+1	SIMPLE	t2	p0,p1,p2	eq_ref	PRIMARY	PRIMARY	4	const	#	100.00	Using where
 Warnings:
-Note	1003	/* select#1 */ select (`sf_add_1`('8') - 1) AS `sf_add_1(a) - 1`,`sf_add_hello`('8') AS `sf_add_hello(b)` from `test`.`t2` where true
+Note	1003	/* select#1 */ select (`sf_add_1`(`test`.`t2`.`a`) - 1) AS `sf_add_1(a) - 1`,`sf_add_hello`(`test`.`t2`.`b`) AS `sf_add_hello(b)` from `test`.`t2` where (`test`.`t2`.`a` = <cache>((7 + `sf_a_from_t1b_d`('1'))))
 FLUSH STATUS;
 START TRANSACTION;
 SELECT sf_add_1(a) - 1, sf_add_hello(b) FROM t2 WHERE a = 7 + sf_a_from_t1b_d('1');
@@ -5430,9 +5430,9 @@ Handler_read_next	7
 UNLOCK TABLES;
 EXPLAIN SELECT sf_add_1(a) - 1, sf_add_hello(b) FROM t2 WHERE a = sf_a_from_t1b_d('1') AND a = 2;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	#	NULL	Impossible WHERE
+1	SIMPLE	t2	p2	const	PRIMARY	PRIMARY	4	const	#	100.00	NULL
 Warnings:
-Note	1003	/* select#1 */ select (`sf_add_1`(`test`.`t2`.`a`) - 1) AS `sf_add_1(a) - 1`,`sf_add_hello`(`test`.`t2`.`b`) AS `sf_add_hello(b)` from `test`.`t2` where false
+Note	1003	/* select#1 */ select (`sf_add_1`('2') - 1) AS `sf_add_1(a) - 1`,`sf_add_hello`('2') AS `sf_add_hello(b)` from `test`.`t2` where ((2 = `sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
 START TRANSACTION;
 SELECT sf_add_1(a) - 1, sf_add_hello(b) FROM t2 WHERE a = sf_a_from_t1b_d('1') AND a = 2;
@@ -5652,7 +5652,7 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN UPDATE t2 SET b = CONCAT('+', b) WHERE a = sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	UPDATE	t2	p1	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
+1	UPDATE	t2	p0,p1,p2	index	NULL	PRIMARY	4	NULL	#	100.00	Using where
 Warnings:
 Note	1003	update `test`.`t2` set `test`.`t2`.`b` = concat('+',`test`.`t2`.`b`) where (`test`.`t2`.`a` = `sf_a_from_t1b_d`('1'))
 FLUSH STATUS;
@@ -5734,7 +5734,7 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN UPDATE t2 SET b = CONCAT('+', b) WHERE a = 7 + sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	UPDATE	t2	p2	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
+1	UPDATE	t2	p0,p1,p2	index	NULL	PRIMARY	4	NULL	#	100.00	Using where
 Warnings:
 Note	1003	update `test`.`t2` set `test`.`t2`.`b` = concat('+',`test`.`t2`.`b`) where (`test`.`t2`.`a` = (7 + `sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
@@ -5808,9 +5808,9 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN UPDATE t2 SET b = CONCAT('+', b) WHERE a = sf_a_from_t1b_d('1') AND a = 2;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	UPDATE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	#	NULL	Impossible WHERE
+1	UPDATE	t2	p2	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
 Warnings:
-Note	1003	update `test`.`t2` set `test`.`t2`.`b` = concat('+',`test`.`t2`.`b`) where ()
+Note	1003	update `test`.`t2` set `test`.`t2`.`b` = concat('+',`test`.`t2`.`b`) where ((`test`.`t2`.`a` = 2) and (2 = `sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
 START TRANSACTION;
 UPDATE t2 SET b = CONCAT('+', b) WHERE a = sf_a_from_t1b_d('1') AND a = 2;
@@ -6064,7 +6064,7 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN UPDATE t2 SET b = sf_add_hello(b) WHERE a = sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	UPDATE	t2	p1	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
+1	UPDATE	t2	p0,p1,p2	index	NULL	PRIMARY	4	NULL	#	100.00	Using where
 Warnings:
 Note	1003	update `test`.`t2` set `test`.`t2`.`b` = `sf_add_hello`(`test`.`t2`.`b`) where (`test`.`t2`.`a` = `sf_a_from_t1b_d`('1'))
 FLUSH STATUS;
@@ -6146,7 +6146,7 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN UPDATE t2 SET b = sf_add_hello(b) WHERE a = 7 + sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	UPDATE	t2	p2	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
+1	UPDATE	t2	p0,p1,p2	index	NULL	PRIMARY	4	NULL	#	100.00	Using where
 Warnings:
 Note	1003	update `test`.`t2` set `test`.`t2`.`b` = `sf_add_hello`(`test`.`t2`.`b`) where (`test`.`t2`.`a` = (7 + `sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
@@ -6220,9 +6220,9 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN UPDATE t2 SET b = sf_add_hello(b) WHERE a = sf_a_from_t1b_d('1') AND a = 2;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	UPDATE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	#	NULL	Impossible WHERE
+1	UPDATE	t2	p2	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
 Warnings:
-Note	1003	update `test`.`t2` set `test`.`t2`.`b` = `sf_add_hello`(`test`.`t2`.`b`) where ()
+Note	1003	update `test`.`t2` set `test`.`t2`.`b` = `sf_add_hello`(`test`.`t2`.`b`) where ((`test`.`t2`.`a` = 2) and (2 = `sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
 START TRANSACTION;
 UPDATE t2 SET b = sf_add_hello(b) WHERE a = sf_a_from_t1b_d('1') AND a = 2;
@@ -6482,7 +6482,7 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN UPDATE t2 SET a = sf_add_1(a) + 4 WHERE a = sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	UPDATE	t2	p1	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
+1	UPDATE	t2	p0,p1,p2	index	NULL	PRIMARY	4	NULL	#	100.00	Using where; Using temporary
 Warnings:
 Note	1003	update `test`.`t2` set `test`.`t2`.`a` = (`sf_add_1`(`test`.`t2`.`a`) + 4) where (`test`.`t2`.`a` = `sf_a_from_t1b_d`('1'))
 FLUSH STATUS;
@@ -6568,7 +6568,7 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN UPDATE t2 SET a = sf_add_1(a) + 4 WHERE a = 7 + sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	UPDATE	t2	p2	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
+1	UPDATE	t2	p0,p1,p2	index	NULL	PRIMARY	4	NULL	#	100.00	Using where; Using temporary
 Warnings:
 Note	1003	update `test`.`t2` set `test`.`t2`.`a` = (`sf_add_1`(`test`.`t2`.`a`) + 4) where (`test`.`t2`.`a` = (7 + `sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
@@ -6644,9 +6644,9 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN UPDATE t2 SET a = sf_add_1(a) + 4 WHERE a = sf_a_from_t1b_d('1') AND a = 2;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	UPDATE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	#	NULL	Impossible WHERE
+1	UPDATE	t2	p2	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
 Warnings:
-Note	1003	update `test`.`t2` set `test`.`t2`.`a` = (`sf_add_1`(`test`.`t2`.`a`) + 4) where ()
+Note	1003	update `test`.`t2` set `test`.`t2`.`a` = (`sf_add_1`(`test`.`t2`.`a`) + 4) where ((`test`.`t2`.`a` = 2) and (2 = `sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
 START TRANSACTION;
 UPDATE t2 SET a = sf_add_1(a) + 4 WHERE a = sf_a_from_t1b_d('1') AND a = 2;
@@ -6899,7 +6899,7 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN DELETE FROM t2 WHERE a = sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	DELETE	t2	p1	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
+1	DELETE	t2	p0,p1,p2	ALL	NULL	NULL	NULL	NULL	#	100.00	Using where
 Warnings:
 Note	1003	delete from `test`.`t2` where (`test`.`t2`.`a` = `sf_a_from_t1b_d`('1'))
 FLUSH STATUS;
@@ -6977,7 +6977,7 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN DELETE FROM t2 WHERE a = 7 + sf_a_from_t1b_d('1');
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	DELETE	t2	p2	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
+1	DELETE	t2	p0,p1,p2	ALL	NULL	NULL	NULL	NULL	#	100.00	Using where
 Warnings:
 Note	1003	delete from `test`.`t2` where (`test`.`t2`.`a` = (7 + `sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
@@ -7049,9 +7049,9 @@ ROLLBACK;
 UNLOCK TABLES;
 EXPLAIN DELETE FROM t2 WHERE a = sf_a_from_t1b_d('1') AND a = 2;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	DELETE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	#	NULL	Impossible WHERE
+1	DELETE	t2	p2	range	PRIMARY	PRIMARY	4	const	#	100.00	Using where
 Warnings:
-Note	1003	delete from `test`.`t2` where ()
+Note	1003	delete from `test`.`t2` where ((`test`.`t2`.`a` = 2) and (2 = `sf_a_from_t1b_d`('1')))
 FLUSH STATUS;
 START TRANSACTION;
 DELETE FROM t2 WHERE a = sf_a_from_t1b_d('1') AND a = 2;

mysql-test/r/sp.result

@@ -6377,24 +6377,24 @@ Warnings:
 Note	1003	/* select#1 */ select `test`.`t1`.`c1` AS `c1` from `test`.`t1` where (`test`.`t1`.`c1` = 1)
 EXPLAIN SELECT * FROM t1 WHERE c1=f1();
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	NULL	ref	c1	c1	5	const	1	100.00	Using index
+1	SIMPLE	t1	NULL	ref	c1	c1	5	const	1	100.00	Using where; Using index
 Warnings:
-Note	1003	/* select#1 */ select `test`.`t1`.`c1` AS `c1` from `test`.`t1` where (`test`.`t1`.`c1` = `f1`())
+Note	1003	/* select#1 */ select `test`.`t1`.`c1` AS `c1` from `test`.`t1` where (`test`.`t1`.`c1` = <cache>(`f1`()))
 EXPLAIN SELECT * FROM v1 WHERE c1=1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	SIMPLE	t1	NULL	ref	c1	c1	5	const	1	100.00	Using index
 Warnings:
 Note	1003	/* select#1 */ select `test`.`t1`.`c1` AS `c1` from `test`.`t1` where (`test`.`t1`.`c1` = 1)
 EXPLAIN SELECT * FROM v1 WHERE c1=f1();
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	NULL	ref	c1	c1	5	const	1	100.00	Using index
+1	SIMPLE	t1	NULL	ref	c1	c1	5	const	1	100.00	Using where; Using index
 Warnings:
-Note	1003	/* select#1 */ select `test`.`t1`.`c1` AS `c1` from `test`.`t1` where (`test`.`t1`.`c1` = `f1`())
+Note	1003	/* select#1 */ select `test`.`t1`.`c1` AS `c1` from `test`.`t1` where (`test`.`t1`.`c1` = <cache>(`f1`()))
 EXPLAIN SELECT * FROM t1 WHERE c1=f2(10);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	NULL	ref	c1	c1	5	const	1	100.00	Using index
+1	SIMPLE	t1	NULL	ref	c1	c1	5	const	1	100.00	Using where; Using index
 Warnings:
-Note	1003	/* select#1 */ select `test`.`t1`.`c1` AS `c1` from `test`.`t1` where (`test`.`t1`.`c1` = `f2`(10))
+Note	1003	/* select#1 */ select `test`.`t1`.`c1` AS `c1` from `test`.`t1` where (`test`.`t1`.`c1` = <cache>(`f2`(10)))
 EXPLAIN SELECT * FROM t1 WHERE c1=f2(c1);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	SIMPLE	t1	NULL	index	NULL	c1	5	NULL	5	20.00	Using where; Using index

mysql-test/t/partition_locking.test

@@ -2938,6 +2938,11 @@ DROP TABLE t1, t2;
 --echo #
 --echo # Test subqueries/stored functions with UPDATE/DELETE/SELECT
 --echo #
+# Bug#37560280:
+# The EXPLAIN plan for queries with the sf_a_from_t1b_d() function call
+# differs from the actual execution plan because constant folding
+# is performed in the actual plan but not in EXPLAIN.
+
 CREATE TABLE tq (id int PRIMARY KEY auto_increment, query varchar(255), not_select tinyint);
 CREATE TABLE tsq (id int PRIMARY KEY auto_increment, subquery varchar(255), can_be_locked tinyint);
 CREATE TABLE t1 (a int, b varchar(255), PRIMARY KEY (a), KEY (b))

sql/item_func.cc

@@ -8319,6 +8319,8 @@ bool Item_func_sp::val_json(Json_wrapper *result) {
 bool Item_func_sp::execute() {
   THD *thd = current_thd;
 
+  assert(!thd->lex->is_explain() || thd->lex->is_explain_analyze);
+
   Internal_error_handler_holder<View_error_handler, Table_ref> view_handler(
       thd, context->view_error_handler, context->view_error_handler_arg);
 

sql/sql_derived.cc

@@ -1670,7 +1670,7 @@ bool Table_ref::optimize_derived(THD *thd) {
   // at execution time (in fact, it will get confused and crash if it has
   // already been materialized).
   if (!thd->lex->using_hypergraph_optimizer()) {
-    if (materializable_is_const() &&
+    if (materializable_is_const(thd) &&
         (create_materialized_table(thd) || materialize_derived(thd)))
       return true;
   }

sql/sql_lex.h

@@ -729,6 +729,8 @@ class Query_expression {
   bool prepared;   ///< All query blocks in query expression are prepared
   bool optimized;  ///< All query blocks in query expression are optimized
   bool executed;   ///< Query expression has been executed
+  ///< Explain mode: query expression refers stored function
+  bool m_has_stored_program{false};
 
   /// Object to which the result for this query expression is sent.
   /// Not used if we materialize directly into a parent query expression's
@@ -773,6 +775,8 @@ class Query_expression {
   /// multi-level ORDER, i.e. we have a "simple table".
   bool is_simple() const { return m_query_term->term_type() == QT_QUERY_BLOCK; }
 
+  bool has_stored_program() const { return m_has_stored_program; }
+
   /// Values for Query_expression::cleaned
   enum enum_clean_state {
     UC_DIRTY,       ///< Unit isn't cleaned
@@ -4999,4 +5003,12 @@ Table_ref *nest_join(THD *thd, Query_block *select, Table_ref *embedding,
                      mem_root_deque<Table_ref *> *jlist, size_t table_cnt,
                      const char *legend);
 void get_select_options_str(ulonglong options, std::string *str);
+
+template <typename T>
+inline bool WalkQueryExpression(Query_expression *query_expr, enum_walk walk,
+                                T &&functor) {
+  return query_expr->walk(&Item::walk_helper_thunk<T>, walk,
+                          reinterpret_cast<uchar *>(&functor));
+}
+
 #endif /* SQL_LEX_INCLUDED */

sql/sql_optimizer.cc

@@ -5696,12 +5696,16 @@ bool JOIN::extract_const_tables() {
            1. are dependent upon other tables, or
            2. have no exact statistics, or
            3. are full-text searched
+           4. a derived table which has a stored function
         */
+        const bool explain_mode = thd->lex->is_explain();
         if ((table->s->system || table->file->stats.records <= 1 ||
              all_partitions_pruned_away) &&
             !tab->dependent &&                                              // 1
             (table->file->ha_table_flags() & HA_STATS_RECORDS_IS_EXACT) &&  // 2
-            !tl->is_fulltext_searched())                                    // 3
+            !tl->is_fulltext_searched() &&                                  // 3
+            !(explain_mode && tl->is_view_or_derived() &&
+              tl->has_stored_program()))  // 4
           mark_const_table(tab, nullptr);
         break;
     }
@@ -5855,6 +5859,7 @@ bool JOIN::extract_func_dependent_tables() {
              6. are not going to be used, typically because they are streamed
                 instead of materialized
                 (see Query_expression::can_materialize_directly_into_result()).
+             7. key evaluated in stored program in EXPLAIN mode
           */
           if (eq_part.is_prefix(table->key_info[key].user_defined_key_parts) &&
               !tl->is_fulltext_searched() &&                            // 1
@@ -5863,7 +5868,9 @@ bool JOIN::extract_func_dependent_tables() {
               !(tab->join_cond() &&
                 tab->join_cond()->cost().IsExpensive()) &&                // 4
               !(table->file->ha_table_flags() & HA_BLOCK_CONST_TABLE) &&  // 5
-              table->is_created()) {                                      // 6
+              table->is_created() &&                                      // 6
+              !(thd->lex->is_explain() &&
+                start_keyuse->val->has_stored_program())) {  // 7
             if (table->key_info[key].flags & HA_NOSAME) {
               if (const_ref == eq_part) {  // Found everything for ref.
                 ref_changed = true;
@@ -6296,7 +6303,7 @@ static ha_rows get_quick_record_count(THD *thd, JOIN_TAB *tab, ha_rows limit,
       return 0;
     }
     DBUG_PRINT("warning", ("Couldn't use record count on const keypart"));
-  } else if (tl->is_table_function() || tl->materializable_is_const()) {
+  } else if (tl->is_table_function() || tl->materializable_is_const(thd)) {
     tl->fetch_number_of_rows();
     return tl->table->file->stats.records;
   }
@@ -11510,6 +11517,13 @@ bool evaluate_during_optimization(const Item *item, const Query_block *select) {
   // If the Item does not access any tables, it can always be evaluated.
   if (item->const_item()) return true;
 
+  // Do not evaluate stored procedure in EXPLAIN
+  if (current_thd->lex->is_explain() &&
+      WalkItem(item, enum_walk::PREFIX, [](const Item *curitem) {
+        return curitem->has_stored_program();
+      }))
+    return false;
+
   return !item->has_subquery() || (select->active_options() &
                                    OPTION_NO_SUBQUERY_DURING_OPTIMIZATION) == 0;
 }

sql/sql_select.cc

@@ -2385,8 +2385,9 @@ bool init_ref_part(THD *thd, unsigned part_no, Item *val, bool *cond_guard,
                                    key_part_info, key_buff, nullable);
   if (unlikely(!s_key || thd->is_error())) return true;
 
-  if (used_tables & ~INNER_TABLE_BIT) {
-    /* Comparing against a non-constant. */
+  if (used_tables & ~INNER_TABLE_BIT ||
+      (thd->lex->is_explain() &&
+       val->has_stored_program())) { /* Comparing against a non-constant. */
     ref->key_copy[part_no] = s_key;
   } else {
     /*