SHOW TABLES FROM information_schema LIKE 'SCHEMATA';
Tables_in_information_schema (SCHEMATA)
SCHEMATA
#######################################################################
# Testcase 3.2.1.1: INFORMATION_SCHEMA tables can be queried via SELECT
#######################################################################
DROP VIEW      IF EXISTS test.v1;
DROP PROCEDURE IF EXISTS test.p1;
DROP FUNCTION  IF EXISTS test.f1;
CREATE VIEW test.v1 AS     SELECT * FROM information_schema.SCHEMATA;
CREATE PROCEDURE test.p1() SELECT * FROM information_schema.SCHEMATA;
CREATE FUNCTION test.f1() returns BIGINT
BEGIN
DECLARE counter BIGINT DEFAULT NULL;
SELECT COUNT(*) INTO counter FROM information_schema.SCHEMATA;
RETURN counter;
END//
# Attention: The printing of the next result sets is disabled.
SELECT * FROM information_schema.SCHEMATA;
SELECT * FROM test.v1;
CALL test.p1;
SELECT test.f1();
DROP VIEW test.v1;
DROP PROCEDURE test.p1;
DROP FUNCTION test.f1;
#########################################################################
# Testcase 3.2.9.1: INFORMATION_SCHEMA.SCHEMATA layout;
#########################################################################
DESCRIBE          information_schema.SCHEMATA;
Field	Type	Null	Key	Default	Extra
CATALOG_NAME	varchar(64)	YES		NULL	
SCHEMA_NAME	varchar(64)	YES		NULL	
DEFAULT_CHARACTER_SET_NAME	varchar(64)	NO		NULL	
DEFAULT_COLLATION_NAME	varchar(64)	NO		NULL	
SQL_PATH	binary(0)	YES		NULL	
DEFAULT_ENCRYPTION	enum('NO','YES')	NO		NULL	
SHOW CREATE TABLE information_schema.SCHEMATA;
View	Create View	character_set_client	collation_connection
SCHEMATA	CREATE ALGORITHM=UNDEFINED DEFINER=`mysql.infoschema`@`localhost` SQL SECURITY DEFINER VIEW `information_schema`.`SCHEMATA` AS select (`cat`.`name` collate utf8_tolower_ci) AS `CATALOG_NAME`,(`sch`.`name` collate utf8_tolower_ci) AS `SCHEMA_NAME`,`cs`.`name` AS `DEFAULT_CHARACTER_SET_NAME`,`col`.`name` AS `DEFAULT_COLLATION_NAME`,NULL AS `SQL_PATH`,`sch`.`default_encryption` AS `DEFAULT_ENCRYPTION` from (((`mysql`.`schemata` `sch` join `mysql`.`catalogs` `cat` on((`cat`.`id` = `sch`.`catalog_id`))) join `mysql`.`collations` `col` on((`sch`.`default_collation_id` = `col`.`id`))) join `mysql`.`character_sets` `cs` on((`col`.`character_set_id` = `cs`.`id`))) where (0 <> can_access_database(`sch`.`name`))	utf8	utf8_general_ci
SHOW COLUMNS FROM information_schema.SCHEMATA;
Field	Type	Null	Key	Default	Extra
CATALOG_NAME	varchar(64)	YES		NULL	
SCHEMA_NAME	varchar(64)	YES		NULL	
DEFAULT_CHARACTER_SET_NAME	varchar(64)	NO		NULL	
DEFAULT_COLLATION_NAME	varchar(64)	NO		NULL	
SQL_PATH	binary(0)	YES		NULL	
DEFAULT_ENCRYPTION	enum('NO','YES')	NO		NULL	
SELECT catalog_name, schema_name, sql_path
FROM information_schema.schemata
WHERE catalog_name IS NOT NULL or sql_path IS NOT NULL
ORDER BY schema_name;
CATALOG_NAME	SCHEMA_NAME	SQL_PATH
def	information_schema	NULL
def	mtr	NULL
def	mysql	NULL
def	performance_schema	NULL
def	sys	NULL
def	test	NULL
###############################################################################
# Testcases 3.2.9.2+3.2.9.3: INFORMATION_SCHEMA.SCHEMATA accessible information
###############################################################################
DROP DATABASE IF EXISTS db_datadict_1;
DROP DATABASE IF EXISTS db_datadict_2;
CREATE DATABASE db_datadict_1 charset latin1;
CREATE DATABASE db_datadict_2 charset latin1;
DROP   USER 'testuser1'@'localhost';
CREATE USER 'testuser1'@'localhost';
DROP   USER 'testuser2'@'localhost';
CREATE USER 'testuser2'@'localhost';
DROP   USER 'testuser3'@'localhost';
CREATE USER 'testuser3'@'localhost';
GRANT SELECT ON db_datadict_1.* to 'testuser1'@'localhost';
GRANT SELECT ON db_datadict_1.* to 'testuser2'@'localhost';
GRANT SELECT ON db_datadict_2.* to 'testuser2'@'localhost';
SELECT * FROM information_schema.schemata
WHERE schema_name LIKE 'db_datadict_%' ORDER BY schema_name;
CATALOG_NAME	SCHEMA_NAME	DEFAULT_CHARACTER_SET_NAME	DEFAULT_COLLATION_NAME	SQL_PATH	DEFAULT_ENCRYPTION
def	db_datadict_1	latin1	latin1_swedish_ci	NULL	NO
def	db_datadict_2	latin1	latin1_swedish_ci	NULL	NO
SHOW DATABASES LIKE 'db_datadict_%';
Database (db_datadict_%)
db_datadict_1
db_datadict_2
# Establish connection testuser1 (user=testuser1)
SELECT * FROM information_schema.schemata
WHERE schema_name LIKE 'db_datadict_%' ORDER BY schema_name;
CATALOG_NAME	SCHEMA_NAME	DEFAULT_CHARACTER_SET_NAME	DEFAULT_COLLATION_NAME	SQL_PATH	DEFAULT_ENCRYPTION
def	db_datadict_1	latin1	latin1_swedish_ci	NULL	NO
SHOW DATABASES LIKE 'db_datadict_%';
Database (db_datadict_%)
db_datadict_1
# Establish connection testuser2 (user=testuser2)
SELECT * FROM information_schema.schemata
WHERE schema_name LIKE 'db_datadict_%' ORDER BY schema_name;
CATALOG_NAME	SCHEMA_NAME	DEFAULT_CHARACTER_SET_NAME	DEFAULT_COLLATION_NAME	SQL_PATH	DEFAULT_ENCRYPTION
def	db_datadict_1	latin1	latin1_swedish_ci	NULL	NO
def	db_datadict_2	latin1	latin1_swedish_ci	NULL	NO
SHOW DATABASES LIKE 'db_datadict_%';
Database (db_datadict_%)
db_datadict_1
db_datadict_2
# Establish connection testuser3 (user=testuser3)
SELECT * FROM information_schema.schemata
WHERE schema_name LIKE 'db_datadict_%' ORDER BY schema_name;
CATALOG_NAME	SCHEMA_NAME	DEFAULT_CHARACTER_SET_NAME	DEFAULT_COLLATION_NAME	SQL_PATH	DEFAULT_ENCRYPTION
SHOW DATABASES LIKE 'db_datadict_%';
Database (db_datadict_%)
# Switch to connection default and close connections testuser1,testuser2,testuser3
DROP USER 'testuser1'@'localhost';
DROP USER 'testuser2'@'localhost';
DROP USER 'testuser3'@'localhost';
DROP DATABASE db_datadict_1;
DROP DATABASE db_datadict_2;
#################################################################################
# Testcases 3.2.1.13+3.2.1.14+3.2.1.15: INFORMATION_SCHEMA.SCHEMATA modifications
#################################################################################
DROP DATABASE IF EXISTS db_datadict;
SELECT * FROM information_schema.schemata WHERE schema_name = 'db_datadict';
CATALOG_NAME	SCHEMA_NAME	DEFAULT_CHARACTER_SET_NAME	DEFAULT_COLLATION_NAME	SQL_PATH	DEFAULT_ENCRYPTION
CREATE DATABASE db_datadict CHARACTER SET 'latin1' COLLATE 'latin1_swedish_ci';
SELECT * FROM information_schema.schemata WHERE schema_name = 'db_datadict';
CATALOG_NAME	SCHEMA_NAME	DEFAULT_CHARACTER_SET_NAME	DEFAULT_COLLATION_NAME	SQL_PATH	DEFAULT_ENCRYPTION
def	db_datadict	latin1	latin1_swedish_ci	NULL	NO
SELECT schema_name, default_character_set_name
FROM information_schema.schemata WHERE schema_name = 'db_datadict';
SCHEMA_NAME	DEFAULT_CHARACTER_SET_NAME
db_datadict	latin1
ALTER SCHEMA db_datadict CHARACTER SET 'utf8';
Warnings:
Warning	3719	'utf8' is currently an alias for the character set UTF8MB3, but will be an alias for UTF8MB4 in a future release. Please consider using UTF8MB4 in order to be unambiguous.
SELECT schema_name, default_character_set_name
FROM information_schema.schemata WHERE schema_name = 'db_datadict';
SCHEMA_NAME	DEFAULT_CHARACTER_SET_NAME
db_datadict	utf8
ALTER SCHEMA db_datadict CHARACTER SET 'latin1';
SELECT schema_name, default_collation_name FROM information_schema.schemata
WHERE schema_name = 'db_datadict';
SCHEMA_NAME	DEFAULT_COLLATION_NAME
db_datadict	latin1_swedish_ci
ALTER SCHEMA db_datadict COLLATE 'latin1_general_cs';
SELECT schema_name, default_collation_name FROM information_schema.schemata
WHERE schema_name = 'db_datadict';
SCHEMA_NAME	DEFAULT_COLLATION_NAME
db_datadict	latin1_general_cs
SELECT schema_name
FROM information_schema.schemata WHERE schema_name = 'db_datadict';
SCHEMA_NAME
db_datadict
DROP DATABASE db_datadict;
SELECT schema_name
FROM information_schema.schemata WHERE schema_name = 'db_datadict';
SCHEMA_NAME
########################################################################
# Testcases 3.2.1.3-3.2.1.5 + 3.2.1.8-3.2.1.12: INSERT/UPDATE/DELETE and
#           DDL on INFORMATION_SCHEMA tables are not supported
########################################################################
DROP DATABASE IF EXISTS db_datadict;
CREATE DATABASE db_datadict CHARACTER SET 'latin1' COLLATE 'latin1_swedish_ci';
INSERT INTO information_schema.schemata
(catalog_name, schema_name, default_character_set_name, sql_path)
VALUES (NULL, 'db1', 'latin1', NULL);
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
INSERT INTO information_schema.schemata
SELECT * FROM information_schema.schemata;
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
UPDATE information_schema.schemata
SET default_character_set_name = 'utf8'
WHERE schema_name = 'db_datadict';
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
UPDATE information_schema.schemata SET catalog_name = 't_4711';
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
DELETE FROM information_schema.schemata WHERE schema_name = 'db_datadict';
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
TRUNCATE information_schema.schemata;
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
CREATE INDEX i1 ON information_schema.schemata(schema_name);
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
ALTER TABLE information_schema.schemata ADD f1 INT;
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
DROP TABLE information_schema.schemata;
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
ALTER TABLE information_schema.schemata RENAME db_datadict.schemata;
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
ALTER TABLE information_schema.schemata RENAME information_schema.xschemata;
ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema'
DROP DATABASE db_datadict;