On 26 Feb 2012, at 4:06pm, Rita <rmorgan...@gmail.com> wrote: > if I can have a primary key of t+user (which would be ideal) how can I do a > search? Can I do a key partial key scan in sqlite? For instance, give me > the record for user 'foo' from time 'x to y' ?
The technical answer to this is that you can search a table for any data in it. Just phrase the 'WHERE' clause of your SELECT correctly and it's up to the SQL engine to figure out how best to do the search. But it would be nice to know whether the search could be done efficiently, so ... If you want to do searches for a specific user and a time range, then you will get fastest results if you have a key of (user, t) not (t, user). This might be a better primary key. Or you might want to keep your primary key as it is, and CREATE an INDEX for this order. If you want to reason these things out, think of listing the data as if you were printing a telephone directory. For the most efficient searches you want all the records you're looking for to appear in one continuous run. So figure out an index order which will list them that way. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
