If I have a set of primary keys (let's say a few hundred) and need to fetch data from the table rows with those keys, what's the fastest way to do so? The options seem to be:
(a) Execute "SELECT … FROM table WHERE key=?", once for each key. (b) Execute "SELECT key, … FROM table WHERE key IN (…)", including all of the key strings. If I do (a), I can pre-prepare the statement and save the overhead of compilation. But SQLite has to go through the rest of its work (starting the virtual machine, b-tree lookup, etc.) once for each key. If I do (b), SQLite has less setup work to do, and it could potentially optimize the b-tree lookup. On the downside, I have to prepare a statement every time since the RHS of an "IN" isn't substitutable. Does anyone have intuition or actual knowledge about which approach is better? Or know of a 3rd better approach? —Jens _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
