When an event handler is triggered, a temporary internal connection is made on which the event handler is executed. The handler is not executed on the connection that caused the handler to be triggered, so statements such as MESSAGE...TO CLIENT, which interact with the client application, are not meaningful within event handlers. Similarly, statements that return result sets are not permitted.
The temporary connection on which the handler is executed does not count towards the connection limit for licensing purposes, and the procedure specified by the login_procedure option is not executed for event connections.
Event handlers execute on a separate connection, with the privileges of the event owner. You can also call a procedure from within the event handler, in which case the procedure executes with the privileges of procedure owner. The separate connection for the event handler does not count towards the ten-connection limit of the personal database server.
Any event errors are logged to the database server message log.
The transaction in an event handler is committed if no errors are detected during execution, and rolled back if errors are detected. See Exception handling and atomic compound statements.
Discuter à propos de cette page dans DocCommentXchange.
|Copyright © 2013, SAP AG ou société affiliée SAP - SAP Sybase SQL Anywhere 16.0|