"NTFS uses B-Tree dir" - Yes, and the next operation system will use SQL for the file system (ever wonder why?) . but NTFS is still slow - based on my experience on exactly such problem!
"The backup issue" - backing up only the file names without the files is nothing more than a corrupted backup! If you think that the image backup is large, consider incremental backups! "Compelling reason" - there are at least 3: - One search instead of two. You search the image (name) in the database. If the image is not stored in the same record in a blob field, you have to initiate a second search in the file system. - Un-corrupted backups. - Unless you make a sophisticated active directory scheme, the image files have to reside in the same computer. Using blobs in a database you may scale the application to hold the database in very fast (and large) server, keeping the application in a separate application server. Horia _____ From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Glenn B. Lawler Sent: Saturday, April 23, 2005 2:40 PM To: '[email protected]' Subject: RE: [delphi-en] Re: Archive ideas wanted. > actual file size might be 1400 bytes and the disk storage allocated is > close to twice that. As was also mentioned previously when you try to Is the file system Fat32? The default cluster size for NTFS is 512 bytes, which means the disk space used to store a file will never be more than 511 bytes more than the actual size. Also, NTFS uses B-Tree directories (like a database) which means that load time in Explorer and the search time to open a file is very quick even when the number of files is very large. The cluster size issue also exists within a database. One of the biggest reasons I avoid using blobs is the backup issue. It is common to have a very large number of image files taking up a very large amount of space. If these files change very infrequently (new files are added frequently but the existing one are infrequently updated), it is easy to design a backup scheme that is very fast. If you store these blobs in the database, the database dump size will become very large and will take a long time to save and load. So far, no one has indicated a compelling reason to include blob data in a database in favor of a reference to the file. I am not saying I would never consider including blob data in a database, but I have never had a situation where there was any advantage to do so. Glenn Lawler ----------------------------------------------------- Home page: http://groups.yahoo.com/group/delphi-en/ To unsubscribe: [EMAIL PROTECTED] _____ Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/delphi-en/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> * Your use of Yahoo! Groups is subject to the Yahoo! <http://docs.yahoo.com/info/terms/> Terms of Service. [Non-text portions of this message have been removed] ----------------------------------------------------- Home page: http://groups.yahoo.com/group/delphi-en/ To unsubscribe: [EMAIL PROTECTED] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/delphi-en/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
