I have a 10GB database and the dump takes just a few minutes. I want to know how the system of dump works ? Someone can tell me ?
-
3Given decently-fast storage, why on earth should it take longer?– MadHatterSep 3, 2014 at 4:58
-
1That said, Assoumani, you don't seem to be picking your questions well, judging by the response you're getting from the community. I strongly recommend that you read our help documents - they're linked from the top of every page - particularly the guide to asking on-topic questions and the guide to asking good questions. You may also find that database questions are better handled on our sister site, dba.stackexchange.com (though you should check their equivalent guides, too).– MadHatterSep 3, 2014 at 5:09
1 Answer
Database consists of data and indices. Sometimes index can be really big. If DB have a number of big indices, then data itself is only a small part of DB.
mysqldump
exports only data, not the indices. When DB is restored from the dump, indices are rebuilt from the scratch. Therefore 10GB DB can produce only 2GB dump. Or even less.