Frequentrly Asked Questions

Q: How CD Duplibase detects duplicates?

A: When you add Volume to database, CD Duplibase read contents of every file and calculates number called CRC32 of the file. CRC32 stores in database. On searching duplicates, when two files has equal CRC32, this means that contents of this files identical (files is duplicates).

Q: How many Volumes can database hold?

A: Database can hold about 100,000 Volumes, it depends on number of files in every Volume.

Q: How to rename database Volume?

A: Right-click on Volume name, click "Properties" menu item, edit volume name and click "OK" or "Apply" button.

Q: How to delete Volume from database?

A: Right-click on Volume name, click "Delete from database" menu item.

Q: Where database files physically located? Can I change database path?

A: Click on "Options" button on main toolbar. In the top edit box you can check and change database path. After you change database path, please click OK and restart CD Duplibase, to avoid errors.

Q: Why adding to database process is so long (about 8-10 minutes for 1 CD)?

A: That's because CD Duplibase is not a simple cataloger, but CD indexing system. It reads contents of every file to calculate CRC32. After, instead of comparing contents of every file, CD Duplibase compares CRC32 of it.

Q: Why some dialog and menu items are disabled?

A: Some items are disabled because they are not implemented yet. They 'll be enabled in the next release. Some items are disabled because of limitations of trial version. Buy full version of CD Duplibase.

Q: How about a "true byte-by-byte comparison" file finders? Are this better than CRC32 comparison?

A: "Byte-by-byte comparison" and CRC32 gives the same results in most cases. The probability of getting "false duplicates" with CRC32 is very small, less than 1%. Additionaly, "Byte-by-byte comparison" require much longer time to compare, because it reads all file contents instead of simply comparing two CRC32 numbers. Only with using CRC32 is possible to compare many files very fast, actually not reading contents of this files.

Q: How can I import/export database contents?

A: You can export volume to CSV file by right-clicking to it and by selecting "Export to...". You can import CSV file by selecting in menu Database->Import from...

Q: What is CSV file format?

A: CSV is an acronym for "Comma Separated Values". A CSV File is a plain text datafile (you can drag/drop one to Windows Notepad and you will see it as plain text). Each row of text represents one "data item". Each field is separated by a comma. Each row in a CSV list one file. The format of each row is: [FileName], [FileSize], [CRC32], [Path], [Comment (optional)].

Q: How about using MD5 hash instead of CRC32?

A: Indeed MD5 gives better results and helps to avoid false duplicates. MD5 is widely used in p2p programs (like EMule/EDonkey), so it useful to use MD5. But CRC32 also widely used in file collection programs, so since version 1.5 CD Duplibase uses both CRC32 and MD5.