"Denis Sbragion" <[EMAIL PROTECTED]> wrote: > Furthermore having both a reader > and a writer at the same time the MVCC "better than row level locking" > mechanism might provide you better performances than SQLite, but here the > devil's in the detail.
"D. Richard Hipp" <[EMAIL PROTECTED]> wrote: > Since PostgreSQL supports READ COMMITTED isolation by default, the > writer lock will not be a problem there. But you will have the same > issue on PosgreSQL if you select SERIALIZABLE isolation. SQLite only > does SERIALIZABLE for database connections running in separate > processes. To combine and clarify our remarks: If you use READ COMMITTED isolation (the default in PostgreSQL) then your writes are not atomic as seen by the reader. In other words, if a burst of inserts occurs while a read is in process, the read might end up seeing some old data from before the burst and some new data from afterwards. This may or may not be a problem for you depending on your application. If it is a problem, then you need to select SERIALIZABLE isolation in PostgreSQL in which case the MVCC is not going to give you any advantage over SQLite. -- D. Richard Hipp <[EMAIL PROTECTED]>
