CHECK LOG FILE
|This command does not require any parameters|
The CHECK LOG FILE command has the same effect as the Check Log File... command of the File menu of 4th Dimension in User mode: it displays the dialog box for viewing the current log file of the database:
This dialog box includes the Rollback button that can be used to cancel operations carried out on the data of the database. For more infromation about this dialog box, please refer to the User Reference manual of 4th Dimension.
Note: Since the rollback function is relatively powerful, it is recommended that access to the CHECK LOG FILE command be restricted to the database administrators.
This command can only be used in the context of single-user applications. More particularly, it allows access to the rollback function from 4D Runtime applications (applications with no User mode). If it is called within a client/server application, the command has no effect and the error 1421 is returned.
Note: The Check Log File... menu command is always available on the server machine.
Backup management system errors, RESTORE.
If this command is executed in a database operating without a log file, it does nothing and the error 1403 is returned.
If this command is executed in a client/server database, it does nothing and the error 1421 is returned.
If this command is called when a transaction or indexing operation is underway in one of the active processes, its execution will be delayed for a period set on the Backup/Backup page of the application Preferences. If, at the end of this waiting period, the operation is still not terminated, the execution of this command is cancelled and the error 1422 is returned.
You can intercept these errors using an error-handling method installed with the ON ERR CALL command.