### test creating index with data contains null field
set @save_sql_mode=@@sql_mode;
==========================================================
# case 1 with hidden primary key
==========================================================
# case 1.1 on INT column
==========================================================
CREATE TABLE t1(id INT, a INT);
INSERT INTO t1 VALUES(1, 1), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	1
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: cannot silently convert NULL values, as required in this SQL_MODE. Try ALGORITHM=COPY.
ALTER TABLE t1 ADD PRIMARY KEY(a);
ERROR 23000: Duplicate entry '0' for key 'PRIMARY'
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` int(11) DEFAULT NULL,
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT, a INT);
INSERT INTO t1 VALUES(1, 1), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	1
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` int(11) DEFAULT NULL,
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT, a INT);
INSERT INTO t1 VALUES(1, 1), (2, NULL);
SELECT * FROM t1;
id	a
1	1
2	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` int(11) DEFAULT NULL,
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
==========================================================
# case 1.2 on CHAR COLUMN
==========================================================
CREATE TABLE t1(id INT, a CHAR(10));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: cannot silently convert NULL values, as required in this SQL_MODE. Try ALGORITHM=COPY.
ALTER TABLE t1 ADD PRIMARY KEY(a);
ERROR 23000: Duplicate entry '' for key 'PRIMARY'
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` char(10) COLLATE utf8mb4_general_ci DEFAULT NULL,
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT, a CHAR(10));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` char(10) COLLATE utf8mb4_general_ci DEFAULT NULL,
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT, a CHAR(10));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` char(10) COLLATE utf8mb4_general_ci DEFAULT NULL,
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
==========================================================
# case 1.3 on VARCHAR COLUMN
==========================================================
CREATE TABLE t1(id INT, a VARCHAR(60));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: cannot silently convert NULL values, as required in this SQL_MODE. Try ALGORITHM=COPY.
ALTER TABLE t1 ADD PRIMARY KEY(a);
ERROR 23000: Duplicate entry '' for key 'PRIMARY'
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` varchar(60) COLLATE utf8mb4_general_ci DEFAULT NULL,
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT, a VARCHAR(60));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` varchar(60) COLLATE utf8mb4_general_ci DEFAULT NULL,
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT, a VARCHAR(60));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` varchar(60) COLLATE utf8mb4_general_ci DEFAULT NULL,
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
==========================================================
# case 1.4 on TEXT COLUMN
==========================================================
CREATE TABLE t1(id INT, a TEXT);
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a(2)), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a(4)), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a(10)), ALGORITHM=INPLACE;
ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: cannot silently convert NULL values, as required in this SQL_MODE. Try ALGORITHM=COPY.
ALTER TABLE t1 ADD PRIMARY KEY(a(10));
ERROR 23000: Duplicate entry '' for key 'PRIMARY'
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` text COLLATE utf8mb4_general_ci,
  UNIQUE KEY `a_2` (`a`(4)),
  KEY `a` (`a`(2))
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT, a TEXT);
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a(2)), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a(4)), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a(10)), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 ADD PRIMARY KEY(a(10));
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` text COLLATE utf8mb4_general_ci,
  UNIQUE KEY `a_2` (`a`(4)),
  KEY `a` (`a`(2))
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT, a TEXT);
INSERT INTO t1 VALUES(1, 'a'), (2, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
ALTER TABLE t1 ADD KEY(a(2)), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a(4)), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD PRIMARY KEY(a(10)), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 ADD PRIMARY KEY(a(10));
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) DEFAULT NULL,
  `a` text COLLATE utf8mb4_general_ci,
  UNIQUE KEY `a_2` (`a`(4)),
  KEY `a` (`a`(2))
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
==========================================================
# case 2 with primary key
==========================================================
# case 2.1 on INT column
==========================================================
CREATE TABLE t1(id INT PRIMARY KEY, a INT);
INSERT INTO t1 VALUES(1, 1), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	1
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: cannot silently convert NULL values, as required in this SQL_MODE. Try ALGORITHM=COPY.
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a);
ERROR 23000: Duplicate entry '0' for key 'PRIMARY'
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT PRIMARY KEY, a INT);
INSERT INTO t1 VALUES(1, 1), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	1
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT PRIMARY KEY, a INT);
INSERT INTO t1 VALUES(1, 1), (2, NULL);
SELECT * FROM t1;
id	a
1	1
2	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
==========================================================
# case 2.2 on CHAR column
==========================================================
CREATE TABLE t1(id INT PRIMARY KEY, a CHAR(10));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: cannot silently convert NULL values, as required in this SQL_MODE. Try ALGORITHM=COPY.
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a);
ERROR 23000: Duplicate entry '' for key 'PRIMARY'
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` char(10) COLLATE utf8mb4_general_ci DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT PRIMARY KEY, a CHAR(10));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` char(10) COLLATE utf8mb4_general_ci DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT PRIMARY KEY, a CHAR(10));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` char(10) COLLATE utf8mb4_general_ci DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
==========================================================
# case 2.3 on VARCHAR column
==========================================================
CREATE TABLE t1(id INT PRIMARY KEY, a VARCHAR(60));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: cannot silently convert NULL values, as required in this SQL_MODE. Try ALGORITHM=COPY.
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a);
ERROR 23000: Duplicate entry '' for key 'PRIMARY'
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` varchar(60) COLLATE utf8mb4_general_ci DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT PRIMARY KEY, a VARCHAR(60));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` varchar(60) COLLATE utf8mb4_general_ci DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT PRIMARY KEY, a VARCHAR(60));
INSERT INTO t1 VALUES(1, 'a'), (2, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
ALTER TABLE t1 ADD KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a);
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` varchar(60) COLLATE utf8mb4_general_ci DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`),
  KEY `a` (`a`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
==========================================================
# case 2.4 on TEXT column
==========================================================
CREATE TABLE t1(id INT PRIMARY KEY, a TEXT);
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a(2)), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a(4)), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a(10)), ALGORITHM=INPLACE;
ERROR 0A000: ALGORITHM=INPLACE is not supported. Reason: cannot silently convert NULL values, as required in this SQL_MODE. Try ALGORITHM=COPY.
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a(10));
ERROR 23000: Duplicate entry '' for key 'PRIMARY'
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` text COLLATE utf8mb4_general_ci,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`(4)),
  KEY `a` (`a`(2))
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT PRIMARY KEY, a TEXT);
INSERT INTO t1 VALUES(1, 'a'), (2, NULL), (3, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
3	NULL
ALTER TABLE t1 ADD KEY(a(2)), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a(4)), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a(10)), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a(10));
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` text COLLATE utf8mb4_general_ci,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`(4)),
  KEY `a` (`a`(2))
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;
set sql_mode="STRICT_ALL_TABLES";
Warnings:
Warning	3135	'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
CREATE TABLE t1(id INT PRIMARY KEY, a TEXT);
INSERT INTO t1 VALUES(1, 'a'), (2, NULL);
SELECT * FROM t1;
id	a
1	a
2	NULL
ALTER TABLE t1 ADD KEY(a(2)), ALGORITHM=INPLACE;
ALTER TABLE t1 ADD UNIQUE KEY(a(4)), ALGORITHM=INPLACE;
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a(10)), ALGORITHM=INPLACE;
ERROR 22004: Invalid use of NULL value
ALTER TABLE t1 DROP PRIMARY KEY, ADD PRIMARY KEY(a(10));
ERROR 22004: Invalid use of NULL value
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `a` text COLLATE utf8mb4_general_ci,
  PRIMARY KEY (`id`),
  UNIQUE KEY `a_2` (`a`(4)),
  KEY `a` (`a`(2))
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
DROP TABLE t1;
set sql_mode = @save_sql_mode;