Backporting 273d8eb12c40a6dcd05a8148bdfba3f1fd96e764 Proper fix for disabling warnings in read_statistics_for_table()

9 files changed, 53 insertions, 160 deletions

diff --git a/mysql-test/include/ctype_utf8_ilseq.inc b/mysql-test/include/ctype_utf8_ilseq.inc
index 1bb009f2a8b..3586946659e 100644
--- a/mysql-test/include/ctype_utf8_ilseq.inc
+++ b/mysql-test/include/ctype_utf8_ilseq.inc
@@ -14,6 +14,7 @@ SHOW CREATE TABLE t1;
 
 INSERT INTO t1 (ch) VALUES ('admin'),('admin1');
 SELECT ch FROM t1 WHERE ch='admin𝌆';
+EXPLAIN SELECT ch FROM t1 WHERE ch='admin𝌆';
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch='admin𝌆';
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='admin𝌆';
 DELETE FROM t1;
diff --git a/mysql-test/r/compare.result b/mysql-test/r/compare.result
index ea8111cc3ce..b06847f09ed 100644
--- a/mysql-test/r/compare.result
+++ b/mysql-test/r/compare.result
@@ -100,3 +100,23 @@ CREATE TABLE t1(a INT ZEROFILL);
 SELECT 1 FROM t1 WHERE t1.a IN (1, t1.a) AND t1.a=2;
 1
 DROP TABLE t1;
+CREATE TABLE t1 (a char(2), index (a));
+insert into t1 values ("aa"),("bb");
+select * from t1 where a="aa";
+a
+aa
+select * from t1 where a="aaa";
+a
+select * from t1 where a="aa ";
+a
+aa
+select * from t1 where a>="aaa";
+a
+bb
+explain select * from t1 where a="aaa";
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	a	a	3	const	1	Using where; Using index
+explain select * from t1 where a="aa ";
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ref	a	a	3	const	1	Using where; Using index
+drop table t1;
diff --git a/mysql-test/r/ctype_uca.result b/mysql-test/r/ctype_uca.result
index d3a51c975a2..69611b2a7ed 100644
--- a/mysql-test/r/ctype_uca.result
+++ b/mysql-test/r/ctype_uca.result
@@ -6748,14 +6748,13 @@ t1	CREATE TABLE `t1` (
 INSERT INTO t1 (ch) VALUES ('admin'),('admin1');
 SELECT ch FROM t1 WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
+EXPLAIN SELECT ch FROM t1 WHERE ch='admin𝌆';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch='admin𝌆';
 ch
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 DELETE FROM t1;
 INSERT INTO t1 (ch) VALUES ('a'), ('a?'), ('a??'), ('a???'), ('a????');
 INSERT INTO t1 (ch) VALUES ('ab'),('a?b'),('a??b'),('a???b'),('a????b');
@@ -6771,22 +6770,14 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 ch
 a
@@ -6829,8 +6820,6 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 ch
 a
@@ -6850,14 +6839,10 @@ ab
 az
 aЀ
 aր
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆b' ORDER BY ch;
 ch
 a
@@ -6877,8 +6862,6 @@ ab
 az
 aЀ
 aր
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 ch
 z
@@ -6889,24 +6872,16 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 ch
 z
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆b' ORDER BY ch;
 ch
 z
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 ALTER TABLE t1 DROP KEY ch;
 # 0xD18F would be a good 2-byte character, 0xD1 is an incomplete sequence
 SET @query=CONCAT('SELECT ch FROM t1 WHERE ch=''a', 0xD1,'''');
@@ -6992,14 +6967,13 @@ t1	CREATE TABLE `t1` (
 INSERT INTO t1 (ch) VALUES ('admin'),('admin1');
 SELECT ch FROM t1 WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
+EXPLAIN SELECT ch FROM t1 WHERE ch='admin𝌆';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch='admin𝌆';
 ch
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 DELETE FROM t1;
 INSERT INTO t1 (ch) VALUES ('a'), ('a?'), ('a??'), ('a???'), ('a????');
 INSERT INTO t1 (ch) VALUES ('ab'),('a?b'),('a??b'),('a???b'),('a????b');
@@ -7015,22 +6989,14 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 ch
 a
diff --git a/mysql-test/r/ctype_uca_innodb.result b/mysql-test/r/ctype_uca_innodb.result
index bd6f3b8a21f..7c64f17190e 100644
--- a/mysql-test/r/ctype_uca_innodb.result
+++ b/mysql-test/r/ctype_uca_innodb.result
@@ -23,14 +23,13 @@ t1	CREATE TABLE `t1` (
 INSERT INTO t1 (ch) VALUES ('admin'),('admin1');
 SELECT ch FROM t1 WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
+EXPLAIN SELECT ch FROM t1 WHERE ch='admin𝌆';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch='admin𝌆';
 ch
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 DELETE FROM t1;
 INSERT INTO t1 (ch) VALUES ('a'), ('a?'), ('a??'), ('a???'), ('a????');
 INSERT INTO t1 (ch) VALUES ('ab'),('a?b'),('a??b'),('a???b'),('a????b');
@@ -46,22 +45,14 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 ch
 a
@@ -104,8 +95,6 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 ch
 a
@@ -125,14 +114,10 @@ ab
 az
 aЀ
 aր
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆b' ORDER BY ch;
 ch
 a
@@ -152,8 +137,6 @@ ab
 az
 aЀ
 aր
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 ch
 z
@@ -164,24 +147,16 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 ch
 z
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆b' ORDER BY ch;
 ch
 z
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 ALTER TABLE t1 DROP KEY ch;
 # 0xD18F would be a good 2-byte character, 0xD1 is an incomplete sequence
 SET @query=CONCAT('SELECT ch FROM t1 WHERE ch=''a', 0xD1,'''');
diff --git a/mysql-test/r/ctype_utf8.result b/mysql-test/r/ctype_utf8.result
index fe873a54edb..2f5b0eecc92 100644
--- a/mysql-test/r/ctype_utf8.result
+++ b/mysql-test/r/ctype_utf8.result
@@ -5467,14 +5467,13 @@ t1	CREATE TABLE `t1` (
 INSERT INTO t1 (ch) VALUES ('admin'),('admin1');
 SELECT ch FROM t1 WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
+EXPLAIN SELECT ch FROM t1 WHERE ch='admin𝌆';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch='admin𝌆';
 ch
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 DELETE FROM t1;
 INSERT INTO t1 (ch) VALUES ('a'), ('a?'), ('a??'), ('a???'), ('a????');
 INSERT INTO t1 (ch) VALUES ('ab'),('a?b'),('a??b'),('a???b'),('a????b');
@@ -5490,22 +5489,14 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 ch
 a
@@ -5548,8 +5539,6 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 ch
 a
@@ -5569,14 +5558,10 @@ ab
 az
 aЀ
 aր
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆b' ORDER BY ch;
 ch
 a
@@ -5596,8 +5581,6 @@ ab
 az
 aЀ
 aր
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 ch
 z
@@ -5608,24 +5591,16 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 ch
 z
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆b' ORDER BY ch;
 ch
 z
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 ALTER TABLE t1 DROP KEY ch;
 # 0xD18F would be a good 2-byte character, 0xD1 is an incomplete sequence
 SET @query=CONCAT('SELECT ch FROM t1 WHERE ch=''a', 0xD1,'''');
@@ -5711,14 +5686,13 @@ t1	CREATE TABLE `t1` (
 INSERT INTO t1 (ch) VALUES ('admin'),('admin1');
 SELECT ch FROM t1 WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
+EXPLAIN SELECT ch FROM t1 WHERE ch='admin𝌆';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch='admin𝌆';
 ch
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 DELETE FROM t1;
 INSERT INTO t1 (ch) VALUES ('a'), ('a?'), ('a??'), ('a???'), ('a????');
 INSERT INTO t1 (ch) VALUES ('ab'),('a?b'),('a??b'),('a???b'),('a????b');
@@ -5734,22 +5708,14 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 ch
 a
@@ -5792,8 +5758,6 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 ch
 a
@@ -5813,14 +5777,10 @@ ab
 az
 aЀ
 aր
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch<'a𝌆b' ORDER BY ch;
 ch
 a
@@ -5840,8 +5800,6 @@ ab
 az
 aЀ
 aր
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 ch
 z
@@ -5852,24 +5810,16 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆' ORDER BY ch;
 ch
 z
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ch	ch	183	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch>'a𝌆b' ORDER BY ch;
 ch
 z
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 ALTER TABLE t1 DROP KEY ch;
 # 0xD18F would be a good 2-byte character, 0xD1 is an incomplete sequence
 SET @query=CONCAT('SELECT ch FROM t1 WHERE ch=''a', 0xD1,'''');
@@ -5955,14 +5905,13 @@ t1	CREATE TABLE `t1` (
 INSERT INTO t1 (ch) VALUES ('admin'),('admin1');
 SELECT ch FROM t1 WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
+EXPLAIN SELECT ch FROM t1 WHERE ch='admin𝌆';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch='admin𝌆';
 ch
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='admin𝌆';
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 DELETE FROM t1;
 INSERT INTO t1 (ch) VALUES ('a'), ('a?'), ('a??'), ('a???'), ('a????');
 INSERT INTO t1 (ch) VALUES ('ab'),('a?b'),('a??b'),('a???b'),('a????b');
@@ -5978,22 +5927,14 @@ EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86' for column `test`.`t1`.`ch` at row 1
 EXPLAIN
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	#	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 FORCE KEY (ch) WHERE ch='a𝌆b' ORDER BY ch;
 ch
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9D\x8C\x86b' for column `test`.`t1`.`ch` at row 1
 SELECT ch FROM t1 IGNORE KEY (ch) WHERE ch<'a𝌆' ORDER BY ch;
 ch
 a
diff --git a/mysql-test/r/processlist.result b/mysql-test/r/processlist.result
index ab518d961ef..4be643c1790 100644
--- a/mysql-test/r/processlist.result
+++ b/mysql-test/r/processlist.result
@@ -36,10 +36,6 @@ SELECT INFO, INFO_BINARY, 'xxx😎yyy' AS utf8mb4_string FROM INFORMATION_SCHEMA
 INFO	SELECT INFO, INFO_BINARY, 'xxx????yyy' AS utf8mb4_string FROM INFORMATION_SCHEMA.PROCESSLIST WHERE INFO LIKE '%xxx%yyy%'
 INFO_BINARY	SELECT INFO, INFO_BINARY, 'xxx😎yyy' AS utf8mb4_string FROM INFORMATION_SCHEMA.PROCESSLIST WHERE INFO LIKE '%xxx%yyy%'
 utf8mb4_string	xxx😎yyy
-Warnings:
-Level	Warning
-Code	1366
-Message	Incorrect string value: '\xF0\x9F\x98\x8Eyy...' for column `information_schema`.`(temporary)`.`INFO` at row 1
 #
 # End of 10.1 tests
 #
diff --git a/mysql-test/r/range.result b/mysql-test/r/range.result
index 406e5c774cf..b55b462c8ef 100644
--- a/mysql-test/r/range.result
+++ b/mysql-test/r/range.result
@@ -2077,23 +2077,15 @@ explain
 SELECT * FROM t1 WHERE fd='😁';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9F\x98\x81' for column `test`.`t1`.`fd` at row 1
 SELECT * FROM t1 WHERE fd='😁';
 id	fd
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9F\x98\x81' for column `test`.`t1`.`fd` at row 1
 # The following must not use range access:
 explain select count(*) from t1 where fd <'😁';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ix_fd	ix_fd	63	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9F\x98\x81' for column `test`.`t1`.`fd` at row 1
 select count(*) from t1 where fd <'😁';
 count(*)
 40960
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9F\x98\x81' for column `test`.`t1`.`fd` at row 1
 select count(*) from t1 ignore index (ix_fd) where fd <'😁';
 count(*)
 40960
@@ -2314,8 +2306,6 @@ INSERT INTO t1 VALUES ('a'),('b'),('c'),('d'),('e');
 EXPLAIN SELECT * FROM t1 WHERE a<=>'😎';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9F\x98\x8E' for column `test`.`t1`.`a` at row 1
 DROP TABLE t1;
 #
 # MDEV-10185: Assertion `tree1->keys[key_no] && tree2->keys[key_no]' failed in 
diff --git a/mysql-test/r/range_mrr_icp.result b/mysql-test/r/range_mrr_icp.result
index e31901fdb26..2584fc5a8bf 100644
--- a/mysql-test/r/range_mrr_icp.result
+++ b/mysql-test/r/range_mrr_icp.result
@@ -2079,23 +2079,15 @@ explain
 SELECT * FROM t1 WHERE fd='😁';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9F\x98\x81' for column `test`.`t1`.`fd` at row 1
 SELECT * FROM t1 WHERE fd='😁';
 id	fd
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9F\x98\x81' for column `test`.`t1`.`fd` at row 1
 # The following must not use range access:
 explain select count(*) from t1 where fd <'😁';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	ix_fd	ix_fd	63	NULL	#	Using where; Using index
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9F\x98\x81' for column `test`.`t1`.`fd` at row 1
 select count(*) from t1 where fd <'😁';
 count(*)
 40960
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9F\x98\x81' for column `test`.`t1`.`fd` at row 1
 select count(*) from t1 ignore index (ix_fd) where fd <'😁';
 count(*)
 40960
@@ -2316,8 +2308,6 @@ INSERT INTO t1 VALUES ('a'),('b'),('c'),('d'),('e');
 EXPLAIN SELECT * FROM t1 WHERE a<=>'😎';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
-Warnings:
-Warning	1366	Incorrect string value: '\xF0\x9F\x98\x8E' for column `test`.`t1`.`a` at row 1
 DROP TABLE t1;
 #
 # MDEV-10185: Assertion `tree1->keys[key_no] && tree2->keys[key_no]' failed in 
diff --git a/mysql-test/t/compare.test b/mysql-test/t/compare.test
index d2b2a7e5523..38bda6754d8 100644
--- a/mysql-test/t/compare.test
+++ b/mysql-test/t/compare.test
@@ -94,3 +94,17 @@ DROP TABLE t1;
 CREATE TABLE t1(a INT ZEROFILL);
 SELECT 1 FROM t1 WHERE t1.a IN (1, t1.a) AND t1.a=2;
 DROP TABLE t1;
+
+#
+# Check what happens when comparing to long string
+#
+
+CREATE TABLE t1 (a char(2), index (a));
+insert into t1 values ("aa"),("bb");
+select * from t1 where a="aa";
+select * from t1 where a="aaa";
+select * from t1 where a="aa ";
+select * from t1 where a>="aaa";
+explain select * from t1 where a="aaa";
+explain select * from t1 where a="aa ";
+drop table t1;