Example
Return the current version of the MySQL database:
SELECT VERSION();
Definition and Usage
The VERSION() function returns the current version of the MySQL database, as a string.
Syntax
VERSION()
Tag: mysql command line
MySQL USER Function
Example
Return the current user name and host name for the MySQL connection:
SELECT USER();
Definition and Usage
The USER() function returns the current user name and host name for the MySQL connection.
Syntax
USER()
MySQL SYSTEM_USER Function
Example
Return the current user name and host name for the MySQL connection:
SELECT SYSTEM_USER();
Definition and Usage
The SYSTEM_USER() function returns the current user name and host name for the MySQL connection.
Syntax
SYSTEM_USER()
MySQL SESSION_USER Function
Example
Return the current user name and host name for the MySQL connection:
SELECT SESSION_USER();
Definition and Usage
The SESSION_USER() function returns the current user name and host name for the MySQL connection.
Syntax
SESSION_USER()
MySQL NULLIF Function
Example
Compare two expressions:
SELECT NULLIF(25, 25);
Definition and Usage
The NULLIF() function compares two expressions and returns NULL if they are equal. Otherwise, the first expression is returned.
Syntax
NULLIF(expr1, expr2)
MySQL LAST_INSERT_ID Function
Example
Return the AUTO_INCREMENT id of the last row that has been inserted in a table:
SELECT LAST_INSERT_ID();
Definition and Usage
The LAST_INSERT_ID() function returns the AUTO_INCREMENT id of the last row that has been inserted in a table.
Syntax
LAST_INSERT_ID(expression)
MySQL ISNULL Function
Example
Test whether an expression is NULL:
SELECT ISNULL(NULL);
Definition and Usage
The ISNULL() function returns 1 or 0 depending on whether an expression is NULL.
If expression is NULL, this function returns 1. Otherwise, it returns 0.
Syntax
ISNULL(expression)
MySQL IFNULL Function
Example
Return the specified value IF the expression is NULL, otherwise return the expression:
SELECT IFNULL(NULL, "Iampsp.com");
Definition and Usage
The IFNULL() function returns a specified value if the expression is NULL.
If the expression is NOT NULL, this function returns the expression.
Syntax
IFNULL(expression, alt_value)
MySQL IF Function
Example
Return “YES” if the condition is TRUE, or “NO” if the condition is FALSE:
SELECT IF(500<1000, "YES", "NO");
Definition and Usage
The IF() function returns a value if a condition is TRUE, or another value if a condition is FALSE.
Syntax
IF(condition, value_if_true, value_if_false)
MySQL DATABASE Function
Example
Return the name of the current (default) database:
SELECT DATABASE();
Definition and Usage
The DATABASE() function returns the name of the current database.
If there is no current database, this function returns NULL or “”.
Syntax
DATABASE()