Merge 10.4 into 10.5

9 files changed, 313 insertions, 29 deletions

diff --git a/mysql-test/main/subselect4.result b/mysql-test/main/subselect4.result
index 54716a83b69..3eb3c265b54 100644
--- a/mysql-test/main/subselect4.result
+++ b/mysql-test/main/subselect4.result
@@ -3042,6 +3042,122 @@ a
 3
 2
 drop table t1,t2,t3;
+#
+# MDEV-29139: Redundant IN/ALL/ANY predicand in GROUP BY clause of
+#             IN/ALL/ANY/EXISTS subquery
+#
+create table t1 (a int);
+create table t2 (b int);
+create table t3 (c int);
+create table t4 (d int);
+insert into t1 values (3), (1);
+insert into t2 values (3), (2);
+insert into t3 values (4), (2);
+insert into t4 values (1), (7);
+explain extended select b from t2
+where exists (select c from t3
+group by (select a from t1 where a = 1) in (select d from t4));
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	
+2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	2	100.00	
+Warnings:
+Note	1003	/* select#1 */ select `test`.`t2`.`b` AS `b` from `test`.`t2` where 1
+select b from t2
+where exists (select c from t3
+group by (select a from t1 where a = 1) in (select d from t4));
+b
+3
+2
+prepare stmt from "select b from t2
+where exists (select c from t3
+group by (select a from t1 where a = 1) in (select d from t4))";
+execute stmt;
+b
+3
+2
+execute stmt;
+b
+3
+2
+deallocate prepare stmt;
+explain extended select b from t2
+where exists (select c from t3
+group by (select a from t1 where a = 1) >=
+any (select d from t4));
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	
+2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	2	100.00	
+Warnings:
+Note	1003	/* select#1 */ select `test`.`t2`.`b` AS `b` from `test`.`t2` where 1
+select b from t2
+where exists (select c from t3
+group by (select a from t1 where a = 1) >=
+any (select d from t4));
+b
+3
+2
+explain extended select b from t2
+where exists (select c from t3
+group by (select a from t1 where a = 1) <
+all (select d from t4));
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	
+2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	2	100.00	
+Warnings:
+Note	1003	/* select#1 */ select `test`.`t2`.`b` AS `b` from `test`.`t2` where 1
+select b from t2
+where exists (select c from t3
+group by (select a from t1 where a = 1) <
+all (select d from t4));
+b
+3
+2
+explain extended select b from t2
+where b in (select c from t3
+group by (select a from t1 where a = 1) in (select d from t4));
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	
+1	PRIMARY	<subquery2>	eq_ref	distinct_key	distinct_key	4	func	1	100.00	
+2	MATERIALIZED	t3	ALL	NULL	NULL	NULL	NULL	2	100.00	
+Warnings:
+Note	1003	select `test`.`t2`.`b` AS `b` from `test`.`t2` semi join (`test`.`t3`) where 1
+select b from t2
+where b in (select c from t3
+group by (select a from t1 where a = 1) in (select d from t4));
+b
+2
+explain extended select b from t2
+where b >= any (select c from t3
+group by (select a from t1 where a = 1) in
+(select d from t4));
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
+2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	2	100.00	
+Warnings:
+Note	1003	/* select#1 */ select `test`.`t2`.`b` AS `b` from `test`.`t2` where <nop>(<in_optimizer>(`test`.`t2`.`b`,(/* select#2 */ select min(`test`.`t3`.`c`) from `test`.`t3`) <= <cache>(`test`.`t2`.`b`)))
+select b from t2
+where b >= any (select c from t3
+group by (select a from t1 where a = 1) in
+(select d from t4));
+b
+3
+2
+explain extended select b from t2
+where b <= all (select c from t3
+group by (select a from t1 where a = 1) in
+(select d from t4));
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
+2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	2	100.00	
+Warnings:
+Note	1003	/* select#1 */ select `test`.`t2`.`b` AS `b` from `test`.`t2` where <not>(<in_optimizer>(`test`.`t2`.`b`,<min>(/* select#2 */ select `test`.`t3`.`c` from `test`.`t3`) < <cache>(`test`.`t2`.`b`)))
+select b from t2
+where b <= all (select c from t3
+group by (select a from t1 where a = 1) in
+(select d from t4));
+b
+2
+drop table t1,t2,t3,t4;
 # End of 10.3 tests
 #
 # MDEV-19134: EXISTS() slower if ORDER BY is defined
diff --git a/mysql-test/main/subselect4.test b/mysql-test/main/subselect4.test
index e1a8510b29a..564ca332a2b 100644
--- a/mysql-test/main/subselect4.test
+++ b/mysql-test/main/subselect4.test
@@ -2479,6 +2479,80 @@ eval $q3;
 
 drop table t1,t2,t3;
 
+--echo #
+--echo # MDEV-29139: Redundant IN/ALL/ANY predicand in GROUP BY clause of
+--echo #             IN/ALL/ANY/EXISTS subquery
+--echo #
+
+create table t1 (a int);
+create table t2 (b int);
+create table t3 (c int);
+create table t4 (d int);
+
+insert into t1 values (3), (1);
+insert into t2 values (3), (2);
+insert into t3 values (4), (2);
+insert into t4 values (1), (7);
+
+let $q1=
+select b from t2
+  where exists (select c from t3
+                group by (select a from t1 where a = 1) in (select d from t4));
+
+eval explain extended $q1;
+eval $q1;
+
+eval prepare stmt from "$q1";
+execute stmt;
+execute stmt;
+deallocate prepare stmt;
+
+let $q2=
+select b from t2
+  where exists (select c from t3
+                group by (select a from t1 where a = 1) >=
+                          any (select d from t4));
+
+eval explain extended $q2;
+eval $q2;
+
+let $q3=
+select b from t2
+  where exists (select c from t3
+                group by (select a from t1 where a = 1) <
+                          all (select d from t4));
+
+eval explain extended $q3;
+eval $q3;
+
+let $q4=
+select b from t2
+  where b in (select c from t3
+              group by (select a from t1 where a = 1) in (select d from t4));
+
+eval explain extended $q4;
+eval $q4;
+
+let $q5=
+select b from t2
+  where b >= any (select c from t3
+                  group by (select a from t1 where a = 1) in
+                            (select d from t4));
+
+eval explain extended $q5;
+eval $q5;
+
+let $q6=
+select b from t2
+  where b <= all (select c from t3
+                  group by (select a from t1 where a = 1) in
+                            (select d from t4));
+
+eval explain extended $q6;
+eval $q6;
+
+drop table t1,t2,t3,t4;
+
 --echo # End of 10.3 tests
 
 --echo #
diff --git a/mysql-test/suite/innodb/r/foreign_key_not_windows.result b/mysql-test/suite/innodb/r/foreign_key_not_windows.result
index 764ba911214..aaff06f8d68 100644
--- a/mysql-test/suite/innodb/r/foreign_key_not_windows.result
+++ b/mysql-test/suite/innodb/r/foreign_key_not_windows.result
@@ -11,6 +11,21 @@ CREATE TABLE `d255`.`_##################################################`
 ERROR HY000: Long database name and identifier for object resulted in path length exceeding 512 characters. Path: './@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023/_@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023@0023
 CREATE TABLE `d255`.`##################################################`
 (a INT PRIMARY KEY, FOREIGN KEY(a) REFERENCES test.t(a)) ENGINE=InnoDB;
+#
+# MDEV-29258 Failing assertion for name length on RENAME TABLE
+#
+CREATE TABLE `d255`.`d245` (x INT) ENGINE=InnoDB;
+DROP TABLE `d255`.`d250`;
+RENAME TABLE `d250#`.`d245` TO `d250#`.`d250`;
+RENAME TABLE `d255`.`d250` TO a;
+DROP TABLE a,t;
+#
+# MDEV-29409 Buffer overflow in my_wc_mb_filename() on RENAME TABLE
+#
+CREATE TABLE `d255`.t(a INT PRIMARY KEY)ENGINE=InnoDB;
+CREATE TABLE `d255`.u(a INT PRIMARY KEY,
+CONSTRAINT `d320` FOREIGN KEY (a) REFERENCES `d255`.t (a)) ENGINE=InnoDB;
+RENAME TABLE `d255`.u TO u;
+DROP TABLE u;
 DROP DATABASE `d255`;
-DROP TABLE t;
 # End of 10.3 tests
diff --git a/mysql-test/suite/innodb/t/foreign_key_not_windows.test b/mysql-test/suite/innodb/t/foreign_key_not_windows.test
index 7ad3723d5de..e5f42a0ddab 100644
--- a/mysql-test/suite/innodb/t/foreign_key_not_windows.test
+++ b/mysql-test/suite/innodb/t/foreign_key_not_windows.test
@@ -38,8 +38,40 @@ eval CREATE TABLE `$d255`.`_$d250`
 --replace_result $d255 d255
 eval CREATE TABLE `$d255`.`$d250`
 (a INT PRIMARY KEY, FOREIGN KEY(a) REFERENCES test.t(a)) ENGINE=InnoDB;
+
+--echo #
+--echo # MDEV-29258 Failing assertion for name length on RENAME TABLE
+--echo #
+
+let $d245=-------------------------------------------------;
+--replace_result $d245 d245 $d255 d255
+eval CREATE TABLE `$d255`.`$d245` (x INT) ENGINE=InnoDB;
+--replace_result $d250 d250 $d255 d255
+eval DROP TABLE `$d255`.`$d250`;
+
+--replace_result $d245 d245 $d250 d250 d255 d255
+eval RENAME TABLE `$d255`.`$d245` TO `$d255`.`$d250`;
+--replace_result $d250 d250 $d255 d255
+eval RENAME TABLE `$d255`.`$d250` TO a;
+--replace_result $d255 d255
+DROP TABLE a,t;
+
+--echo #
+--echo # MDEV-29409 Buffer overflow in my_wc_mb_filename() on RENAME TABLE
+--echo #
+
+let $d225=#############################################;
+let $d320=################################################################;
+
+--replace_result $d255 d255
+eval CREATE TABLE `$d255`.t(a INT PRIMARY KEY)ENGINE=InnoDB;
+--replace_result $d255 d255 $d320 d320
+eval CREATE TABLE `$d255`.u(a INT PRIMARY KEY,
+CONSTRAINT `$d320` FOREIGN KEY (a) REFERENCES `$d255`.t (a)) ENGINE=InnoDB;
+--replace_result $d255 d255
+eval RENAME TABLE `$d255`.u TO u;
+DROP TABLE u;
 --replace_result $d255 d255
 eval DROP DATABASE `$d255`;
-DROP TABLE t;
 
 --echo # End of 10.3 tests
diff --git a/mysql-test/suite/innodb/t/innodb_sys_semaphore_waits.test b/mysql-test/suite/innodb/t/innodb_sys_semaphore_waits.test
index a0b9fc626f3..29ff3f69ed7 100644
--- a/mysql-test/suite/innodb/t/innodb_sys_semaphore_waits.test
+++ b/mysql-test/suite/innodb/t/innodb_sys_semaphore_waits.test
@@ -78,10 +78,10 @@ let $counter= 80;
 let $mysql_errno= 0;
 while (!$mysql_errno)
 {
-  --error 0,ER_SERVER_SHUTDOWN,ER_CONNECTION_KILLED,2002,2006,2013
+  --error 0,ER_SERVER_SHUTDOWN,ER_CONNECTION_KILLED,2002,2006,2013,5014
   show status;
 
-  --error 0,ER_SERVER_SHUTDOWN,ER_CONNECTION_KILLED,2002,2006,2013
+  --error 0,ER_SERVER_SHUTDOWN,ER_CONNECTION_KILLED,2002,2006,2013,5014
   select * from information_schema.innodb_sys_semaphore_waits;
 
   dec $counter;
diff --git a/mysql-test/suite/innodb_fts/r/innodb_fts_plugin.result b/mysql-test/suite/innodb_fts/r/innodb_fts_plugin.result
index 0a408ab4ce7..83c5066a898 100644
--- a/mysql-test/suite/innodb_fts/r/innodb_fts_plugin.result
+++ b/mysql-test/suite/innodb_fts/r/innodb_fts_plugin.result
@@ -1,4 +1,5 @@
 INSTALL PLUGIN simple_parser SONAME 'mypluglib';
+FLUSH TABLES;
 # Test Part 1: Grammar Test
 CREATE TABLE articles (
 id INT UNSIGNED AUTO_INCREMENT NOT NULL PRIMARY KEY,
@@ -31,7 +32,7 @@ INSERT INTO articles (title, body) VALUES
 ('1001 MySQL Tricks','How to use full-text search engine'),
 ('Go MySQL Tricks','How to use full text search engine');
 SELECT * FROM articles WHERE
-MATCH(title, body) AGAINST('mysql');
+MATCH(title, body) AGAINST('mysql') ORDER BY id;
 id	title	body
 1	MySQL Tutorial	DBMS stands for MySQL DataBase ...
 2	How To Use MySQL Well	After you went through a ...
@@ -68,7 +69,7 @@ INSERT INTO articles (title, body) VALUES
 ('Go MySQL Tricks','How to use full text search engine');
 ALTER TABLE articles ADD FULLTEXT INDEX (title, body) WITH PARSER simple_parser;
 SELECT * FROM articles WHERE
-MATCH(title, body) AGAINST('mysql');
+MATCH(title, body) AGAINST('mysql') ORDER BY id;
 id	title	body
 1	MySQL Tutorial	DBMS stands for MySQL DataBase ...
 2	How To Use MySQL Well	After you went through a ...
@@ -88,21 +89,23 @@ MATCH(title, body) AGAINST('full text');
 id	title	body
 5	Go MySQL Tricks	How to use full text search engine
 SELECT * FROM articles WHERE
-MATCH(title, body) AGAINST('full-text' WITH QUERY EXPANSION);
+MATCH(title, body) AGAINST('full-text' WITH QUERY EXPANSION)
+ORDER BY id;
 id	title	body
-4	1001 MySQL Tricks	How to use full-text search engine
-5	Go MySQL Tricks	How to use full text search engine
-2	How To Use MySQL Well	After you went through a ...
 1	MySQL Tutorial	DBMS stands for MySQL DataBase ...
+2	How To Use MySQL Well	After you went through a ...
 3	Optimizing MySQL	In this tutorial we will show ...
+4	1001 MySQL Tricks	How to use full-text search engine
+5	Go MySQL Tricks	How to use full text search engine
 SELECT * FROM articles WHERE
-MATCH(title, body) AGAINST('full text' WITH QUERY EXPANSION);
+MATCH(title, body) AGAINST('full text' WITH QUERY EXPANSION)
+ORDER BY id;
 id	title	body
-5	Go MySQL Tricks	How to use full text search engine
-4	1001 MySQL Tricks	How to use full-text search engine
-2	How To Use MySQL Well	After you went through a ...
 1	MySQL Tutorial	DBMS stands for MySQL DataBase ...
+2	How To Use MySQL Well	After you went through a ...
 3	Optimizing MySQL	In this tutorial we will show ...
+4	1001 MySQL Tricks	How to use full-text search engine
+5	Go MySQL Tricks	How to use full text search engine
 SELECT * FROM articles WHERE
 MATCH(title, body) AGAINST('"mysql database"' IN BOOLEAN MODE);
 id	title	body
@@ -137,27 +140,27 @@ INSERT INTO articles (title, body) VALUES
 ('Go MariaDB Tricks','How to use full text search engine');
 # restart
 SELECT * FROM articles WHERE
-MATCH(title, body) AGAINST('MySQL');
+MATCH(title, body) AGAINST('MySQL') ORDER BY id;
 id	title	body
 6	MySQL Tutorial	DBMS stands for MySQL DataBase ...
 7	How To Use MySQL Well	After you went through a ...
 8	Optimizing MySQL	In this tutorial we will show ...
 9	1001 MySQL Tricks	How to use full-text search engine
 SELECT * FROM articles WHERE
-MATCH(title, body) AGAINST('tutorial');
+MATCH(title, body) AGAINST('tutorial') ORDER BY id;
 id	title	body
 6	MySQL Tutorial	DBMS stands for MySQL DataBase ...
 8	Optimizing MySQL	In this tutorial we will show ...
 SELECT * FROM articles WHERE
-MATCH(title, body) AGAINST('Tricks');
+MATCH(title, body) AGAINST('Tricks') ORDER BY id;
 id	title	body
 9	1001 MySQL Tricks	How to use full-text search engine
 10	Go MariaDB Tricks	How to use full text search engine
 SELECT * FROM articles WHERE
-MATCH(title, body) AGAINST('full text search');
+MATCH(title, body) AGAINST('full text search') ORDER BY id;
 id	title	body
-10	Go MariaDB Tricks	How to use full text search engine
 9	1001 MySQL Tricks	How to use full-text search engine
+10	Go MariaDB Tricks	How to use full text search engine
 SELECT COUNT(*) FROM articles;
 COUNT(*)
 5
@@ -185,7 +188,8 @@ UNINSTALL PLUGIN simple_parser;
 Warnings:
 Warning	1620	Plugin is busy and will be uninstalled on shutdown
 SELECT * FROM articles WHERE
-MATCH(title, body) AGAINST('mysql');
+MATCH(title, body) AGAINST('mysql')
+ORDER BY id;
 id	title	body
 1	MySQL Tutorial	DBMS stands for MySQL DataBase ...
 2	How To Use MySQL Well	After you went through a ...
diff --git a/mysql-test/suite/innodb_fts/t/innodb_fts_plugin.test b/mysql-test/suite/innodb_fts/t/innodb_fts_plugin.test
index b22ac456668..7279925386b 100644
--- a/mysql-test/suite/innodb_fts/t/innodb_fts_plugin.test
+++ b/mysql-test/suite/innodb_fts/t/innodb_fts_plugin.test
@@ -6,6 +6,9 @@
 # Install fts parser plugin
 INSTALL PLUGIN simple_parser SONAME 'mypluglib';
 
+# Flush the table mysql.plugin in case the server shutdown would time out.
+FLUSH TABLES;
+
 -- echo # Test Part 1: Grammar Test
 # Create a myisam table and alter it to innodb table
 CREATE TABLE articles (
@@ -52,7 +55,7 @@ INSERT INTO articles (title, body) VALUES
 
 # Simple term search
 SELECT * FROM articles WHERE
-	MATCH(title, body) AGAINST('mysql');
+	MATCH(title, body) AGAINST('mysql') ORDER BY id;
 
 # Test stopword and word len less than fts_min_token_size
 SELECT * FROM articles WHERE
@@ -90,7 +93,7 @@ ALTER TABLE articles ADD FULLTEXT INDEX (title, body) WITH PARSER simple_parser;
 
 # Simple term search
 SELECT * FROM articles WHERE
-	MATCH(title, body) AGAINST('mysql');
+	MATCH(title, body) AGAINST('mysql') ORDER BY id;
 
 # Test stopword and word len less than fts_min_token_size
 SELECT * FROM articles WHERE
@@ -105,10 +108,12 @@ SELECT * FROM articles WHERE
 
 # Test query expansion
 SELECT * FROM articles WHERE
-	MATCH(title, body) AGAINST('full-text' WITH QUERY EXPANSION);
+	MATCH(title, body) AGAINST('full-text' WITH QUERY EXPANSION)
+	ORDER BY id;
 
 SELECT * FROM articles WHERE
-	MATCH(title, body) AGAINST('full text' WITH QUERY EXPANSION);
+	MATCH(title, body) AGAINST('full text' WITH QUERY EXPANSION)
+	ORDER BY id;
 
 # No result here, we get '"mysql' 'database"' by simple parser
 SELECT * FROM articles WHERE
@@ -150,13 +155,13 @@ INSERT INTO articles (title, body) VALUES
 --source include/restart_mysqld.inc
 
 SELECT * FROM articles WHERE
-         MATCH(title, body) AGAINST('MySQL');
+         MATCH(title, body) AGAINST('MySQL') ORDER BY id;
 SELECT * FROM articles WHERE
-         MATCH(title, body) AGAINST('tutorial');
+         MATCH(title, body) AGAINST('tutorial') ORDER BY id;
 SELECT * FROM articles WHERE
-         MATCH(title, body) AGAINST('Tricks');
+         MATCH(title, body) AGAINST('Tricks') ORDER BY id;
 SELECT * FROM articles WHERE
-         MATCH(title, body) AGAINST('full text search');
+         MATCH(title, body) AGAINST('full text search') ORDER BY id;
 SELECT COUNT(*) FROM articles;
 
 INSERT INTO articles (title, body) VALUES ('111', '1234 1234 1234');
@@ -193,7 +198,8 @@ UNINSTALL PLUGIN simple_parser;
 
 # Simple term search
 SELECT * FROM articles WHERE
-	MATCH(title, body) AGAINST('mysql');
+	MATCH(title, body) AGAINST('mysql')
+	ORDER BY id;
 
 # Test stopword and word len less than fts_min_token_size
 SELECT * FROM articles WHERE
diff --git a/mysql-test/suite/period/r/alter.result b/mysql-test/suite/period/r/alter.result
index 7b9d1fea861..8aa94cee59e 100644
--- a/mysql-test/suite/period/r/alter.result
+++ b/mysql-test/suite/period/r/alter.result
@@ -191,6 +191,20 @@ ERROR 23000: Duplicate entry '1-2020-03-01-2020-03-02' for key 'PRIMARY'
 alter table t1 add system versioning;
 drop table t1;
 #
+# MDEV-18873 Server crashes in Compare_identifiers::operator or in 
+# my_strcasecmp_utf8 upon ADD PERIOD IF NOT EXISTS with empty name
+#
+alter table t add period if not exists for `` (s,e);
+ERROR 42000: Incorrect column name ''
+create table t(s DATE, e DATE);
+alter table t add period if not exists for `` (s,e);
+ERROR 42000: Incorrect column name ''
+alter table t add period if not exists for ` ` (s,e);
+ERROR 42000: Incorrect column name ' '
+create table t2 (period for `` (s,e)) select * from t;
+ERROR 42000: Incorrect column name ''
+drop table t;
+#
 # MDEV-21941 RENAME doesn't work for system time or period fields
 #
 create or replace table t1 (
diff --git a/mysql-test/suite/period/t/alter.test b/mysql-test/suite/period/t/alter.test
index 68d9adf476a..fab933eca87 100644
--- a/mysql-test/suite/period/t/alter.test
+++ b/mysql-test/suite/period/t/alter.test
@@ -153,6 +153,29 @@ alter table t1 add system versioning;
 drop table t1;
 
 --echo #
+--echo # MDEV-18873 Server crashes in Compare_identifiers::operator or in 
+--echo # my_strcasecmp_utf8 upon ADD PERIOD IF NOT EXISTS with empty name
+--echo #
+
+# When there is no table defined.
+--error ER_WRONG_COLUMN_NAME
+alter table t add period if not exists for `` (s,e);
+
+# When there is an actual table.
+create table t(s DATE, e DATE);
+--error ER_WRONG_COLUMN_NAME
+alter table t add period if not exists for `` (s,e);
+
+# When the last character is space
+--error ER_WRONG_COLUMN_NAME
+alter table t add period if not exists for ` ` (s,e);
+
+# Create table with an empty period name
+--error ER_WRONG_COLUMN_NAME
+create table t2 (period for `` (s,e)) select * from t;
+drop table t;
+
+--echo #
 --echo # MDEV-21941 RENAME doesn't work for system time or period fields
 --echo #
 create or replace table t1 (