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(512)	NO		NULL	
SCHEMA_NAME	varchar(64)	NO		NULL	
DEFAULT_CHARACTER_SET_NAME	varchar(32)	NO		NULL	
DEFAULT_COLLATION_NAME	varchar(32)	NO		NULL	
SQL_PATH	varchar(512)	YES		NULL	
SCHEMA_COMMENT	varchar(1024)	NO		NULL	
SHOW CREATE TABLE information_schema.SCHEMATA;
Table	Create Table
SCHEMATA	CREATE TEMPORARY TABLE `SCHEMATA` (
  `CATALOG_NAME` varchar(512) NOT NULL,
  `SCHEMA_NAME` varchar(64) NOT NULL,
  `DEFAULT_CHARACTER_SET_NAME` varchar(32) NOT NULL,
  `DEFAULT_COLLATION_NAME` varchar(32) NOT NULL,
  `SQL_PATH` varchar(512),
  `SCHEMA_COMMENT` varchar(1024) NOT NULL
) ENGINE=MEMORY DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_general_ci
SHOW COLUMNS FROM information_schema.SCHEMATA;
Field	Type	Null	Key	Default	Extra
CATALOG_NAME	varchar(512)	NO		NULL	
SCHEMA_NAME	varchar(64)	NO		NULL	
DEFAULT_CHARACTER_SET_NAME	varchar(32)	NO		NULL	
DEFAULT_COLLATION_NAME	varchar(32)	NO		NULL	
SQL_PATH	varchar(512)	YES		NULL	
SCHEMA_COMMENT	varchar(1024)	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;
CREATE DATABASE db_datadict_2;
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	SCHEMA_COMMENT
def	db_datadict_1	latin1	latin1_swedish_ci	NULL	
def	db_datadict_2	latin1	latin1_swedish_ci	NULL	
SHOW DATABASES LIKE 'db_datadict_%';
Database (db_datadict_%)
db_datadict_1
db_datadict_2
connect  testuser1, localhost, testuser1, , db_datadict_1;
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	SCHEMA_COMMENT
def	db_datadict_1	latin1	latin1_swedish_ci	NULL	
def	db_datadict_2	latin1	latin1_swedish_ci	NULL	
SHOW DATABASES LIKE 'db_datadict_%';
Database (db_datadict_%)
db_datadict_1
db_datadict_2
connect  testuser2, localhost, testuser2, , db_datadict_2;
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	SCHEMA_COMMENT
def	db_datadict_1	latin1	latin1_swedish_ci	NULL	
def	db_datadict_2	latin1	latin1_swedish_ci	NULL	
SHOW DATABASES LIKE 'db_datadict_%';
Database (db_datadict_%)
db_datadict_1
db_datadict_2
connect  testuser3, localhost, testuser3, , test;
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	SCHEMA_COMMENT
def	db_datadict_1	latin1	latin1_swedish_ci	NULL	
def	db_datadict_2	latin1	latin1_swedish_ci	NULL	
SHOW DATABASES LIKE 'db_datadict_%';
Database (db_datadict_%)
db_datadict_1
db_datadict_2
connection default;
disconnect testuser1;
disconnect testuser2;
disconnect 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	SCHEMA_COMMENT
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	SCHEMA_COMMENT
def	db_datadict	latin1	latin1_swedish_ci	NULL	
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';
SELECT schema_name, default_character_set_name
FROM information_schema.schemata WHERE schema_name = 'db_datadict';
schema_name	default_character_set_name
db_datadict	utf8mb3
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 HY000: The target table schemata of the UPDATE is not updatable
UPDATE information_schema.schemata SET catalog_name = 't_4711';
ERROR HY000: The target table schemata of the UPDATE is not updatable
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;