Differences in other SQL features between AnalyticDB for MySQL and MySQL-AnalyticDB(AnalyticDB)-阿里云帮助中心

This page describes SQL features where AnalyticDB for MySQL differs from MySQL 5.6 — either by not supporting them, or by supporting them with different behavior. Even when a statement is listed as "Supported," its semantics may differ from MySQL. Review the notes in each section before migrating.

MySQL 5.6 features not supported by AnalyticDB for MySQL

The following MySQL 5.6 feature categories are not supported:

Database management
- Plug-ins and user-defined functions
- SET
Compound query
Data replication
Stored objects
Transactional and locking statements
User-defined functions

Character sets and collations

AnalyticDB for MySQL supports only UTF-8.

mysql> SHOW CHARACTER SET;
+---------+---------------+-------------------+--------+
| Charset | Description   | Default collation | Maxlen |
+---------+---------------+-------------------+--------+
| utf8    | UTF-8 Unicode | utf8_general_ci   | 3      |
+---------+---------------+-------------------+--------+
1 row in set (0.00 sec)


mysql> SHOW COLLATION;
+-----------------+---------+------+---------+----------+---------+
| Collation       | Charset | Id   | Default | Compiled | Sortlen |
+-----------------+---------+------+---------+----------+---------+
| utf8_general_ci | utf8    |   33 | Yes     | Yes      |       1 |
| binary          | binary  |   63 | Yes     | Yes      |       1 |
+-----------------+---------+------+---------+----------+---------+
2 rows in set (0.00 sec)

Case sensitivity

Data is case-sensitive in AnalyticDB for MySQL, unlike MySQL.

Database management

Important

Some statements listed as "Supported" have behavioral differences from MySQL. Read the notes carefully before using them.

Category	MySQL	AnalyticDB for MySQL	Definition
Account management	ALTER USER	Not supported	Modifies a user.
	CREATE USER	Supported. For more information, see CREATE USER.	Creates a new user.
	DROP USER	Supported. For more information, see DROP USER.	Deletes one or more users and their permissions.
	GRANT	Supported. For more information, see GRANT.	Grants a permission to a user.
	RENAME USER	Supported. For more information, see RENAME USER.	Renames an existing user.
	REVOKE	Supported. For more information, see REVOKE.	Lets a system administrator revoke user permissions.
Table maintenance	ANALYZE TABLE	Supported. The collected statistics differ, but this is transparent to users.	Analyzes and stores the key distribution for a named table.
	CHECK TABLE	Not supported	Checks one or more tables for errors.
	CHECKSUM TABLE	Not supported	Returns the checksum of the table content.
	OPTIMIZE TABLE	Support	Reorganizes the physical storage of table data and associated index data to reduce storage space and improve I/O efficiency when accessing the table.
	REPAIR TABLE	Not supported	Repairs a possibly corrupted table. This operation is only for specific storage engines.
SHOW	SHOW AUTHORS	Not supported	Displays developer information.
	SHOW BINARY LOGS	Not supported	Displays the binary log files on the server.
	SHOW BINLOG EVENTS	Not supported	Displays events in the binary log.
	SHOW CHARACTER	Supported	Displays all available character sets.
	SHOW COLLATION	Supported	Displays the collations supported by the server.
	SHOW COLUMNS FROM	Supported Note AnalyticDB for MySQL does not support filter conditions. For example, the `show columns from xxx` statement displays all columns.	Displays information about the columns in a given table. It also applies to views.
	SHOW CONTRIBUTORS	Not supported	Displays contributors.
	SHOW CREATE DATABASE	Not supported	Displays the statement that creates the database.
	SHOW CREATE EVENT	Not supported	Displays the statement that creates the event.
	SHOW CREATE FUNCTION	Not supported	Displays the statement that creates the function.
	SHOW CREATE PROCEDURE	Not supported	Displays the statement that creates the stored procedure.
	SHOW CREATE TABLE	Support	Displays the statement that creates the table.
	SHOW CREATE TRIGGER	Not supported	Displays the statement that creates the trigger.
	SHOW CREATE VIEW	Support	Displays the statement that creates the view.
	SHOW DATABASES	Support	Displays the databases on the server.
	SHOW ENGINE	Not supported	Displays the log or status information of a storage engine.
	SHOW ENGINES	Not supported	Displays the storage engines that the server currently supports.
	SHOW ERRORS	Not supported	Displays the error messages generated by the last executed statement.
	SHOW EVENTS	Not supported	Displays information about events in the default database.
	SHOW FUNCTION CODE	Not supported	For internal server debugging. Displays the internal implementation of a specified stored function.
	SHOW FUNCTION STATUS	Not supported	Displays information about stored functions. You must create a stored function first.
	SHOW GRANTS	Supported	Displays the access privileges owned by a specified user.
	SHOW INDEX	Supported	Displays index information for a specified database.
	SHOW MASTER STATUS	Not supported	Displays information about the binary log that the master is currently using.
	SHOW OPEN TABLES	Not supported	Displays a list of non-temporary tables that are registered in the table cache and are open.
	SHOW PLUGINS	Not supported	Displays plugin information.
	SHOW PRIVILEGES	Not supported	Displays the privileges that can be granted and their definitions.
	SHOW PROCEDURE CODE	Not supported	For internal server debugging. Displays the internal implementation of a specified stored procedure.
	SHOW PROCEDURE STATUS	Not supported	Displays information about stored procedures. You must create a stored procedure first.
	SHOW PROCESSLIST	Supported. For more information, see SHOW PROCESSLIST.	Displays information about current server activity.
	SHOW PROFILE	Not supported	Displays the resource usage for statements executed in the current session.
	SHOW PROFILES	Not supported	Displays the resource usage for statements executed in the current session.
	SHOW RELAYLOG EVENTS	Not supported	Displays relay log event information. You must set up master-slave replication first.
	SHOW SLAVE HOSTS	Not supported	Displays a list of replication hosts registered on the master host. You must set up master-slave replication first.
	SHOW SLAVE STATUS	Not supported	Displays the status information of the slave host. You must set up master-slave replication first.
	SHOW STATUS	Not supported	Displays MySQL status information.
	SHOW TABLE STATUS	Not supported	Displays table property information.
	SHOW TABLES	Support	Displays the names of all tables in the current database.
	SHOW TRIGGERS	Not supported	Displays trigger information. You must create a trigger first.
	SHOW VARIABLES	Supported	Displays variable information.
	SHOW WARNINGS	Not supported	Displays the warning messages generated by the last executed statement.
Other	BINLOG	Not supported	The BINLOG statement is for internal use.
	CACHE INDEX	Not supported	Assigns table indexes to a specific key cache.
	FLUSH	Support	The FLUSH statement has multiple variants that can clear or reload various internal caches, refresh tables, or acquire locks.
	KILL	Supported. For more information, see KILL PROCESS.	Terminates a running process.
	LOAD INDEX INTO CACHE	Not supported	The LOAD INDEX INTO CACHE statement preloads table indexes into the key cache to which they were assigned by an explicit CACHE INDEX statement, or into the default key cache otherwise.
	RESET	Not supported	Clears the status of various server operations.

Public statements

MySQL	AnalyticDB for MySQL	Definition
DESCRIBE	Supported	Gets information about table schemas.
EXPLAIN	Supported. For more information, see Use the EXPLAIN and EXPLAIN ANALYZE commands to analyze execution plans and SQL diagnostics overview.	Queries execution plans.
HELP	Not supported	Returns online help information from MySQL references.
USE	Supported	Sets a named database as the default (current) database for subsequent statements. Requires permissions on the database or its objects.