Proper fix for disabling warnings in read_statistics_for_table().

MDEV-20589: Server still crashes in Field::set_warning_truncated_wrong_value

- Use dbug_tmp_use_all_columns() to mark that all fields can be used
- Remove field->is_stat_field (not needed)
- Remove extra arguments to Field::clone() that should not be there
- Safety fix for Field::set_warning_truncated_wrong_value() to not crash
  if table is zero in production builds (We have got crashes several times
  here so better to be safe than sorry).
- Threat wrong character string warnings identical to other field
  conversion warnings. This removes some warnings we before got from
  internal conversion errors.  There is no good reason why a user would
  get an error in case of 'key_field='wrong-utf8-string' but not for
  'field=wrong-utf8-string'.  The old code could also easily give
  thousands of no-sence warnings for one single statement.

1 files changed, 3 insertions, 28 deletions

diff --git a/mysql-test/main/ctype_uca_innodb.result b/mysql-test/main/ctype_uca_innodb.result
index bd6f3b8a21f..7c64f17190e 100644
--- a/mysql-test/main/ctype_uca_innodb.result
+++ b/mysql-test/main/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,'''');