MDEV-15035 Wrong results when calling a stored procedure

multiple times with different arguments.

If the ON expression of an outer join is an OR formula with one
of the disjunct being a constant formula then the expression
cannot be null-rejected if the constant formula is true. Otherwise
it can be null-rejected and if so the outer join can be converted
into inner join. This optimization was added in the patch for
mdev-4817. Yet the code had a defect: if the query was used in
a stored procedure with parameters and the constant item contained
some of them then the value of this constant item depended on the
values of the parameters. With some parameters it may be true,
for others not. The validity of conversion to inner join is checked
only once and it happens only for the first call of procedure.
So if the  parameters in the first call allowed the conversion it
was done and next calls used the transformed query though there
could be calls whose parameters made the conversion invalid.

Fixed by cheking whether the constant disjunct in the ON expression
originally contained an SP parameter. If so the expression is not
considered as null-rejected. For this check a new item's attribute
was intruduced: Item::with_param. It is calculated for each item
by fix fields() functions.
Also moved the call of optimize_constant_subqueries() in
JOIN::optimize after the call of simplify_joins(). The reason
for this is that after the optimization introduced by the patch
for mdev-4817 simplify_joins() can use the results of execution
of non-expensive constant subqueries and this is not valid.

1 files changed, 42 insertions, 0 deletions

diff --git a/mysql-test/t/sp-innodb.test b/mysql-test/t/sp-innodb.test
index 23715166a02..e44a853e713 100644
--- a/mysql-test/t/sp-innodb.test
+++ b/mysql-test/t/sp-innodb.test
@@ -158,5 +158,47 @@ SET @@innodb_lock_wait_timeout= @innodb_lock_wait_timeout_saved;
 --echo # BUG 16041903: End of test case
 --echo #
 
+--echo #
+--echo # MDEV-15035: SP using query with outer join and a parameter
+--echo #             in ON expression
+--echo #
+
+CREATE TABLE t1 (
+	id int NOT NULL,
+	PRIMARY KEY (id)
+) ENGINE=InnoDB;
+
+INSERT INTO t1 VALUES (1), (2);
+
+CREATE TABLE t2 (
+	id int NOT NULL,
+	id_foo int NOT NULL,
+	PRIMARY KEY (id)
+) ENGINE=InnoDB;
+
+INSERT INTO t2 VALUES (1, 1);
+
+--disable_warnings
+DROP PROCEDURE IF EXISTS test_proc;
+--enable_warnings
+
+DELIMITER |;
+CREATE PROCEDURE test_proc(IN param int)
+LANGUAGE SQL
+READS SQL DATA
+BEGIN
+	SELECT DISTINCT f.id
+	FROM t1 f
+	LEFT OUTER JOIN t2 b ON b.id_foo = f.id
+	WHERE (param <> 0 OR b.id IS NOT NULL);
+END|
+DELIMITER ;|
+
+CALL test_proc(0);
+CALL test_proc(1);
+
+DROP PROCEDURE IF EXISTS test_proc;
+DROP TABLE t1, t2;
+
 # Wait till we reached the initial number of concurrent sessions
 --source include/wait_until_count_sessions.inc