SQLite rocks, its definitely the way to go. Its binary is around 250K, but it supports more of the SQL standard than MySQL. It CAN be thread safe, but you have to compile it with a threadsafe macro enabled.. check out www.sqlite.org for more info. The windows binaries apparently are compiled with this option, but the Linux binaries are not, so if you're on Linux, you'll have to compile it yourself, which isn't hard.
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