信息函数用于返回动态的数据库信息,本文介绍了PolarDB-X 1.0支持及不支持的信息函数。

支持函数

PolarDB-X 1.0支持如下信息函数:

函数名 描述
CONNECTION_ID() Return the connection ID (thread ID) for the connection
CURRENT_USER(), CURRENT_USER The authenticated user name and host name
DATABASE() Return the default (current) database name
LAST_INSERT_ID() Value of the AUTOINCREMENT column for the last INSERT
SCHEMA() Synonym for DATABASE()
SESSION_USER() Synonym for USER()
SYSTEM_USER() Synonym for USER()
USER() The user name and host name provided by the client
VERSION() Return a string that indicates the MySQL server version

不支持函数

与 MySQL5.7 相比,PolarDB-X 1.0暂不支持如下信息函数:

函数 描述
BENCHMARK() Repeatedly execute an expression
CHARSET() Return the character set of the argument
COERCIBILITY() Return the collation coercibility value of the string argument
COLLATION() Return the collation of the string argument
FOUND_ROWS() For a SELECT with a LIMIT clause, the number of rows that would be returned were there no LIMIT clause
ROW_COUNT() The number of rows updated