On Fri, Jul 18, 2014 at 6:44 PM, David Canterbrie <[email protected]> wrote:
> Hello, > > I've been tasked with trying to understand how much of a performance hit > one would get if one had to scan a table in its entirety versus reading the > same data stored as a new-line (or some sort like that) from a file. > > The hypothesis I suppose we're trying to understand is that reading > sequentially from SQLite (without indices) should be comparable to reading > from a file that has the same data +/- 1-2% > Hard to say. There are a lot of dependencies. In a test of reading BLOBs out of an SQLite database (seen at http://www.sqlite.org/intern-v-extern-blob.html) we find that SQLite can be up to 2.5x faster or 4x slower than direct file I/O depending on the BLOB size and the page size of the database file. > > My first question is that does sound reasonable, and has someone ever done > such a test? > > Secondly, is this even a valid test? Would someone want to store non > indexed data in SQLite table? > > The next test is where it gets interesting -- i.e. if we were to add an > index, how does full scan performance degrade -- does SQLite have an option > to maintain an index as a separate file? So that all the data can be stored > sequentially? > > Dave > _______________________________________________ > sqlite-users mailing list > [email protected] > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > -- D. Richard Hipp [email protected] _______________________________________________ sqlite-users mailing list [email protected] http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
