Conditions may arise during stored program execution that require special handling, such as exiting the current program block or continuing execution. Handlers can be defined for general conditions such as warnings or exceptions, or for specific conditions such as a particular error code. Specific conditions can be assigned names and referred to that way in handlers.

To name a condition, use the DECLARE ... CONDITION statement. To declare a handler, use the DECLARE ... HANDLER statement. See Section 13.6.7.1, “DECLARE ... CONDITION Syntax”, and Section 13.6.7.2, “DECLARE ... HANDLER Syntax”.

Other statements related to conditions are SIGNAL, RESIGNAL, and GET DIAGNOSTICS. The SIGNAL and RESIGNAL statements are not supported until MySQL 5.5. The GET DIAGNOSTICS statement is not supported until MySQL 5.6.