Use this statement to signal an error and to send a message to the client.
RAISERROR error-number [ format-string ] [, arg-list ]
error-number The error-number is a five-digit integer greater than 17000. The error number is stored in the global variable @@error.
format-string If format-string is not supplied or is empty, the error number is used to locate an error message in the system tables. Adaptive Server Enterprise obtains messages 17000-19999 from the SYSMESSAGES table. In SQL Anywhere this table is an empty view, so errors in this range should provide a format string. Messages for error numbers of 20000 or greater are obtained from the ISYSUSERMESSAGE table.
In SQL Anywhere, the format-string length can be up to 255 bytes.
The extended values supported by the Adaptive Server Enterprise RAISERROR statement are not supported in SQL Anywhere.
The format string can contain placeholders for the arguments in the optional argument list. These placeholders are of the form %nn!, where nn is an integer between 1 and 20.
Intermediate RAISERROR status and code information is lost after the procedure terminates. If at return time an error occurs along with the RAISERROR then the error information is returned and the RAISERROR information is lost. The application can query intermediate RAISERROR statuses by examining @@error global variable at different execution points.
The RAISERROR statement allows user-defined errors to be signaled and sends a message on the client.
SQL/2003 Transact-SQL extension.
The following statement raises error 23000, which is in the range for user-defined errors, and sends a message to the client. Note that there is no comma between the error-number and the format-string parameters. The first item following a comma is interpreted as the first item in the argument list.
RAISERROR 23000 'Invalid entry for this column: %1!', @val
The next example uses RAISERROR to disallow connections.
CREATE PROCEDURE DBA.login_check() BEGIN // Allow a maximum of 3 concurrent connections IF( DB_PROPERTY('ConnCount') > 3 ) THEN RAISERROR 28000 'User %1! is not allowed to connect -- there are ' || 'already %2! users logged on', Current User, CAST( DB_PROPERTY( 'ConnCount' ) AS INT )-1; ELSE CALL sp_login_environment; END IF; END go GRANT EXECUTE ON DBA.login_check TO PUBLIC go SET OPTION PUBLIC.login_procedure='DBA.login_check' go
For an alternate way to disallow connections, see login_procedure option [database].