New topic: Deleting the oldest file in a directory
<http://forums.realsoftware.com/viewtopic.php?t=46703> Page 1 of 1 [ 2 posts ] Previous topic | Next topic Author Message RonBower Post subject: Deleting the oldest file in a directoryPosted: Fri Jan 25, 2013 7:35 pm Joined: Wed Feb 01, 2012 3:06 pm Posts: 47 This forum has been of tremendous help so I have come back for more advice. In my application, I have a RealSQLDatabase and I want to keep a reasonable number of backups in case the user decides to back out something he has done or needs to try to recover from some type of error. So far, I have written code that creates a copy of the database file every time the user commits records to the database. The routine seems to be working okay and the final part of the project will be to provide a user interface to open the contents of the backup folder and choose a file to use to recover data. What I want to do next, however, is to start the deleting oldest backup file whenever I create a new one and exceed some preset limit. Say, for example, that I set a limit of 50 backup files. So, after I create a backup file I then check how many files are in the backup folder. If I find more than 50, then I want to delete the oldest backup file. I've read some of the cautions in the Language Reference about some of the procedures being time consuming so want to request advice. What would be an efficient way to find the oldest file in a directory and delete it ? My current thought is to get the file count and then use the FolderItem.Item method on the folder to examine each file, save the creation date of each, and after going though all in the folder delete the oldest that I found. Is there a smoother way to find and delete the oldest file in a directory ? Ron Bower Ellicott City, MD Top Sky Stream Post subject: Re: Deleting the oldest file in a directoryPosted: Fri Jan 25, 2013 10:01 pm Joined: Sun Nov 23, 2008 12:27 am Posts: 373 Location: New Jersey I written an application that does something similar to what you are looking to do. In a nutshell: 1) perform a recursive scan through your directory and store the file absolute path , file date to a database table. 2) run a query against this table to figure out what items you can delete and output it out to a recordset. 3) loop through the recordset and delete the files. I think for something like this.. let sql do the heavy lifting of helping you decide what can be deleted. On another note.. that is a lot of overhead if you are planning to backup a database after every commit. you might be better off looking at incorporating change control in the db design. _________________ - Rich Top Display posts from previous: All posts1 day7 days2 weeks1 month3 months6 months1 year Sort by AuthorPost timeSubject AscendingDescending Page 1 of 1 [ 2 posts ] -- Over 1500 classes with 29000 functions in one REALbasic plug-in collection. The Monkeybread Software Realbasic Plugin v9.3. http://www.monkeybreadsoftware.de/realbasic/plugins.shtml rbforumnotifier@monkeybreadsoftware.de
