On Mon, Apr 21, 2014 at 9:30 AM, Drago, William @ MWG - NARDAEAST < william.dr...@l-3com.com> wrote:
> All, > > One of the tables in my database has 4 columns that will hold small (under > 5K) BLOBs. In many cases there will be no data at all in one or more of > these columns (see sample below). Does this present any kind of problem? No. Two things to be aware of: (1) When reading a row, SQLite reads from beginning to end. So if you have some small integer or boolean fields, it is better to put them first in the table. Otherwise, SQLite has to read past the big BLOBs in order to get to the smaller fields, even if the BLOBs themselves are not used. (2) When changing any column of a row, the entire row is rewritten, including the unchanged columns. So if you have some smaller fields (integers and booleans) that change frequently and also some large BLOBs that change infrequently, you might consider factoring the BLOBs out into a separate table just so they don't have to be rewritten every time a boolean in the same row changes. Both points above a purely performance considerations. You should always get the correct answer either way. -- D. Richard Hipp d...@sqlite.org _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
