Warren Young writes: > This version of Cygwin SQLite also makes one other big, potentially > breaking change: temporary files are created in-memory exclusively, by > default.
I've been reading the documentation for that option again and it appears that eventually the temporary table _will_ be committed to disk anyway when it exceeds some size threshold (or SQLite runs out of page buffers), so it looks that whatever problems with creating or using such an actual file should manifest itself before the table gets that large. This would also explain why there is no strong warning about this potentially breaking with large temporary tables, I'd think. > There is some concern that this could cause problems with huge DB > files on 32-bit Cygwin. If this version of SQLite fails with some > out-of-memory error with your DB, there is a pragma you can set to > make it behave the old way: > > https://www.sqlite.org/pragma.html#pragma_temp_store > > If setting this pragma to 1 fixes such an error, I want to hear it! > (I'd also be curious to know how big the DB file is, and how much RAM > there is in your machine.) A new version of DBD::SQLite was released just recently, so I took the occasion and built it against the test version of sqlite3 today. I've added "pragma TEMP_STORE=1" to the test that originally triggered the "treat Cygwin as UNIX" saga and this still works, not setting CYGWIN_SQLITE_LOCKING to anything at all. That test doesn't have concurrency so locking is not really involved, however I can't see why temp table files and locking would interfere at all. I think it would be exceedingly rare that any other process would know the name of the file backing the table or the directory that it lives in. I've lost track of what values use which locking strategy in the latest build, so let me know if I should try a something different as well. Regards, Achim. -- +<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+ Factory and User Sound Singles for Waldorf Q+, Q and microQ: http://Synth.Stromeko.net/Downloads.html#WaldorfSounds -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
