*** 22,27 **** --- 22,35 ---- <p>So if there work in working out joins it stands to reason that doing that work for SQLite will speed up the compile times. If you are returning 100's of rows this might not matter but if you are returning 1 row many times this might be a big issue. (<i>Does anyone understand this paragraph? I don't. It should probably be rewritten or removed.</i>)</p> + <P> I think the above paragraph is pointing out that SQLite translates the JOIN syntax + to WHERE expression clauses before byte-coding. The suggestion is that using + WHERE clauses in your SQL statements will eliminate this step and thus speed + up the compilation of the SQL. This is probably true, but the savings will + be quite miniscule. Perhaps around 2 or 3 + malloc()/free() calls per JOIN clause. PreCompiledSql might be a better trick. + </P> + <H2>Order your tables properly in your where clause</H2> <p>Place the tables where you can eliminate the most rows by using a where clause (preferably on an indexed column) first, in order to limit the number of JOIN operations required.</p>
Small. Fast. Reliable.
Choose any three.
Choose any three.
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