INTEGRATE LOG FILE

version 2004.3

INTEGRATE LOG FILE (pathName)

Preliminary note: This command only works with 4D Server. It can only be executed via the Execute on server command or in a stored procedure.

The INTEGRATE LOG FILE command integrates the log file, whose name or pathname was passed in the pathName parameter, into the current database. Afterwards, the file that was integrated becomes the new current log file of the database. This command is meant to be used for setting up a backup system using a logical mirror (see the section "Setting up a logical mirror" in the 4D Server Reference manual).

Only log files that are not filed (extension .4DL) can be integrated using this command. No dialog box appears; but a progress bar is displayed on screen.

In the pathName parameter, you can pass an absolute pathname or one that is relative to the database folder. If you pass an empty string in this parameter, a standard open file dialog box will be displayed to allow you to indicate the file to be integrated. If this dialog box is cancelled, no file will be integrated and the system variable OK is set to 0.

When using this command, it is up to the developer to:

• Install the mirror database on the mirror machine and make sure that the data file will not be modified other than by the integration of the log file using the INTEGRATE LOG FILE command. In order to detect whether it is the mirror version of the database, it is possible to place a file in the 4D Extensions folder or database folder and to test for its presence for instance during the On Startup database method. If the file is present, the mirror mode is activated.

• Set up a communication system between the operational database and the mirror database in order to organize the sending and receiving of the log file segments. To do this, it is possible to use a Web service, the 4D Open for 4D plug-in or the 4D Internet Commands.

• Handle any possible transmission errors that may occur between the two databases.

New log file.

If the integration is carried out correctly, the system variable OK is set to 1; otherwise, it is set to 0.

In the event of an error, the command generates a code that can be intercepted using the ON ERR CALL command. If there are any locked records in the database, the command does nothing and the error 1420 is generated.