Bug#40127 Multiple table DELETE IGNORE hangs on foreign key constraint violation

          on 5.0            
The server crashes on an assert in net_end_statement indicating that the
Diagnostics area wasn't set properly during execution.
This happened on a multi table DELETE operation using the IGNORE keyword.
The keyword is suppose to allow for execution to continue on a best effort
despite some non-fatal errors. Instead execution stopped and no client
response was sent which would have led to a protocol error if it hadn't been
for the assert.
This patch corrects this issue by checking for the existence of an IGNORE
option before setting an error state during row-by-row delete iteration.


mysql-test/r/innodb_mysql.result:
  * Added test case for bug40127
mysql-test/t/innodb_mysql.test:
  * Added test case for bug40127
sql/sql_delete.cc:
  * IGNORE option wasn't implemented in multi_delete::send_data
    and multi_delete::do_deletes

1 files changed, 145 insertions, 0 deletions

diff --git a/mysql-test/r/innodb_mysql.result b/mysql-test/r/innodb_mysql.result
index 6fcc9415d12..55dc0d51142 100644
--- a/mysql-test/r/innodb_mysql.result
+++ b/mysql-test/r/innodb_mysql.result
@@ -1846,4 +1846,149 @@ id
 TRUNCATE TABLE t2;
 DROP TABLE t2;
 DROP TABLE t1;
+#
+# Bug#40127 Multiple table DELETE IGNORE hangs on foreign key constraint violation on 5.0
+#
+CREATE TABLE t1 (
+id INT UNSIGNED NOT NULL AUTO_INCREMENT,
+PRIMARY KEY (id)
+) ENGINE=InnoDB;
+CREATE TABLE t2 (
+id INT UNSIGNED NOT NULL AUTO_INCREMENT,
+aid INT UNSIGNED NOT NULL,
+PRIMARY KEY (id),
+FOREIGN KEY (aid) REFERENCES t1 (id)
+) ENGINE=InnoDB;
+CREATE TABLE t3 (
+bid INT UNSIGNED NOT NULL,
+FOREIGN KEY (bid) REFERENCES t2 (id)
+) ENGINE=InnoDB;
+CREATE TABLE t4 (
+a INT
+) ENGINE=InnoDB;
+CREATE TABLE t5 (
+a INT
+) ENGINE=InnoDB;
+INSERT INTO t1 (id) VALUES (1);
+INSERT INTO t2 (id, aid) VALUES (1, 1),(2,1),(3,1),(4,1);
+INSERT INTO t3 (bid) VALUES (1);
+INSERT INTO t4 VALUES (1),(2),(3),(4),(5);
+INSERT INTO t5 VALUES (1);
+DELETE t5 FROM t4 LEFT JOIN t5 ON t4.a= t5.a;
+DELETE t2, t1 FROM t2 INNER JOIN t1 ON (t2.aid = t1.id) WHERE t2.id = 1;
+ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`t3`, CONSTRAINT `t3_ibfk_1` FOREIGN KEY (`bid`) REFERENCES `t2` (`id`))
+DELETE t2, t1 FROM t2 INNER JOIN t1 ON (t2.aid = t1.id) WHERE t2.id = 1;
+ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`t3`, CONSTRAINT `t3_ibfk_1` FOREIGN KEY (`bid`) REFERENCES `t2` (`id`))
+DELETE IGNORE t2, t1 FROM t2 INNER JOIN t1 ON (t2.aid = t1.id) WHERE t2.id = 1;
+DROP TABLE t3;
+DROP TABLE t2;
+DROP TABLE t1;
+DROP TABLES t4,t5;
+# Bug#40127 Multiple table DELETE IGNORE hangs on foreign key constraint violation on 5.0
+# Testing for any side effects of IGNORE on AFTER DELETE triggers used with
+# transactional tables.
+#
+CREATE TABLE t1 (i INT NOT NULL PRIMARY KEY) ENGINE=InnoDB;
+CREATE TABLE t2 (a VARCHAR(100)) ENGINE=InnoDB;
+CREATE TABLE t3 (i INT NOT NULL PRIMARY KEY) ENGINE=InnoDB;
+CREATE TABLE t4 (i INT NOT NULL PRIMARY KEY, t1i INT, 
+FOREIGN KEY (t1i) REFERENCES t1(i))
+ENGINE=InnoDB;
+CREATE TRIGGER trg AFTER DELETE ON t1 FOR EACH ROW
+BEGIN
+SET @b:='EXECUTED TRIGGER';
+INSERT INTO t2 VALUES (@b);
+SET @a:= error_happens_here;
+END||
+SET @b:="";
+SET @a:="";
+INSERT INTO t1 VALUES (1),(2),(3),(4);
+INSERT INTO t3 SELECT * FROM t1;
+** An error in a trigger causes rollback of the statement.
+DELETE t1 FROM t3 LEFT JOIN t1 ON t1.i=t3.i;
+ERROR 42S22: Unknown column 'error_happens_here' in 'field list'
+SELECT @a,@b;
+@a	@b
+	EXECUTED TRIGGER
+SELECT * FROM t2;
+a
+SELECT * FROM t1 LEFT JOIN t3 ON t1.i=t3.i;
+i	i
+1	1
+2	2
+3	3
+4	4
+** Same happens with the IGNORE option
+DELETE IGNORE t1 FROM t3 LEFT JOIN t1 ON t1.i=t3.i;
+ERROR 42S22: Unknown column 'error_happens_here' in 'field list'
+SELECT * FROM t2;
+a
+SELECT * FROM t1 LEFT JOIN t3 ON t1.i=t3.i;
+i	i
+1	1
+2	2
+3	3
+4	4
+**
+** The following is an attempt to demonstrate
+** error handling inside a row iteration.
+**
+DROP TRIGGER trg;
+TRUNCATE TABLE t1;
+TRUNCATE TABLE t2;
+TRUNCATE TABLE t3;
+INSERT INTO t1 VALUES (1),(2),(3),(4);
+INSERT INTO t3 VALUES (1),(2),(3),(4);
+INSERT INTO t4 VALUES (3,3),(4,4);
+CREATE TRIGGER trg AFTER DELETE ON t1 FOR EACH ROW
+BEGIN
+SET @b:= CONCAT('EXECUTED TRIGGER FOR ROW ',CAST(OLD.i AS CHAR));
+INSERT INTO t2 VALUES (@b);
+END||
+** DELETE is prevented by foreign key constrains but errors are silenced.
+** The AFTER trigger isn't fired.
+DELETE IGNORE t1 FROM t3 LEFT JOIN t1 ON t1.i=t3.i;
+** Tables are modified by best effort:
+SELECT * FROM t1 LEFT JOIN t3 ON t1.i=t3.i;
+i	i
+3	3
+4	4
+** The AFTER trigger was only executed on successful rows:
+SELECT * FROM t2;
+a
+EXECUTED TRIGGER FOR ROW 1
+EXECUTED TRIGGER FOR ROW 2
+DROP TRIGGER trg;
+**
+** Induce an error midway through an AFTER-trigger
+**
+TRUNCATE TABLE t4;
+TRUNCATE TABLE t1;
+TRUNCATE TABLE t3;
+INSERT INTO t1 VALUES (1),(2),(3),(4);
+INSERT INTO t3 VALUES (1),(2),(3),(4);
+CREATE TRIGGER trg AFTER DELETE ON t1 FOR EACH ROW
+BEGIN
+SET @a:= @a+1;
+IF @a > 2 THEN
+INSERT INTO t4 VALUES (5,5);
+END IF;
+END||
+SET @a:=0;
+** Errors in the trigger causes the statement to abort.
+DELETE IGNORE t1 FROM t3 LEFT JOIN t1 ON t1.i=t3.i;
+ERROR 23000: Cannot add or update a child row: a foreign key constraint fails (`test`.`t4`, CONSTRAINT `t4_ibfk_1` FOREIGN KEY (`t1i`) REFERENCES `t1` (`i`))
+SELECT * FROM t1 LEFT JOIN t3 ON t1.i=t3.i;
+i	i
+1	1
+2	2
+3	3
+4	4
+SELECT * FROM t4;
+i	t1i
+DROP TRIGGER trg;
+DROP TABLE t4;
+DROP TABLE t1;
+DROP TABLE t2;
+DROP TABLE t3;
 End of 5.1 tests