Name
DECLARE
Synopsis
DECLAREvariable
data_type
[DEFAULTvalue
] DECLAREcondition
CONDITION FOR {SQLSTATE [VALUE]value
|error_code
] DECLAREcursor
CURSOR FOR SELECT... DECLARE {CONTINUE|EXIT|UNDO} HANDLER FOR {[SQLSTATE [VALUE]value
] [SQLWARNING] [NOT FOUND] [SQLEXCEPTION] [error_code
] [condition
]}SQL_statement
This statement declares local variables and other items
related to routines. It must be used within a BEGIN...END compound statement of a routine, after
BEGIN
and before any other SQL statements. There
are four basic uses for DECLARE
: to declare local
variables, conditions, cursors, and handlers. Within a BEGIN...END block, variables
and conditions must be declared before cursors and handlers, and
cursors must be declared before handlers.
The first syntax shows how to declare variables. It includes the data type and, optionally, default values. A variable declared with this statement is available only within the routine in which it is declared. If the default is a string, place it within quotes. If no default is declared, NULL is the default value.
A condition is generally either an SQLSTATE value or a MySQL
error code number. The second syntax is used for declaring a condition
and associating it with an SQLSTATE or an error code. When declaring a
condition based on an SQLSTATE, give the SQLSTATE
VALUE
clause followed by the state. Otherwise, give the
error code number.
The third syntax declares a cursor, which represents—within a procedure—a results set that is retrieved ...
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