On 04/08/2015 10:52 PM, R.Smith wrote: > > > On 2015-04-08 05:38 PM, Dan Kennedy wrote: >> On 04/08/2015 09:51 PM, R.Smith wrote: >>> >>> >>> On 2015-04-08 04:18 PM, Fabian Pr?bstl wrote: >>>> Hi there! >>>> >>>> Currently, we are using SQLite as our application file format for a >>>> Windows 7/C#/System.Data.SQLite based desktop application. We only >>>> allow one instance to open the file by running "set >>>> locking_mode=EXCLUSIVE;BEGIN EXCLUSIVE;COMMIT" when connecting to >>>> the database. >>> >>> BEGIN EXCLUSIVE - Locks the database from other SQLite3 database >>> connections for the time being. >>> COMMIT; - Unlocks it again - so calling all this in one go is >>> pointless. >> >> Almost always correct. But the "PRAGMA locking_mode=EXCLUSIVE" thing >> changes the behaviour: >> >> https://www.sqlite.org/pragma.html#pragma_locking_mode > > But you need an actual SELECT to get a shared lock and an actual write > operation to lock it exclusively, just starting the transaction and > ending it does nothing to that effect? Or is my understanding wrong?
That's the usual case. But "BEGIN EXCLUSIVE" actually does take an exclusive lock: https://www.sqlite.org/lang_transaction.html
