[EMAIL PROTECTED] writes:

> PostgreSQL has a much better query optimizer than SQLite.
> (You can do that when you have a multi-megabyte memory footprint
> budget versus 250KiB for SQLite.)  In your particular case,
> I would guess you could get SQLite to run as fast or faster
> than PostgreSQL by hand-optimizing your admittedly complex
> queries.

In this light, I had a single query that took about 24 *hours* to complete in
sqlite (2.8.x).  I hand optimized the query by breaking it into multiple (14
I think) separate sequential queries which generate temporary tables for the
next query to work with, and building some indexes on the temporary tables.
The 24 hour query was reduced to a few *seconds*.

Query optimization is critical for large queries in sqlite, and sqlite can be
made VERY fast if you take the time to optimize the queries that are taking a
long time to execute.

Derrell

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