[database-devel] Multi-threaded access to an SQLite database
leon.p.smith at gmail.com
Sat Jan 5 00:10:21 CET 2013
As quick and easy workaround, you could use a single haskell thread
to talk to SQLite, and then snaplet-sqlite-simple code would then
talk to this thread instead of issuing sqlite-simple calls directly.
I've done the same thing to interface with zeromq, using my
On Fri, Jan 4, 2013 at 5:54 PM, Janne Hellsten <jjhellst at gmail.com> wrote:
> Moving the discussion over to database-devel - others may find this
> interesting / may have run into this.
> FWIW - I also tried setting up a test case which would have multiple
> concurrent writers, but couldn't get this to fail. I suspect though
> that my test case wasn't good enough to hit this problem.
> Background: This originated from , also collected some notes on .
> : https://github.com/nurpax/snaplet-sqlite-simple/issues/5
> : here: http://nurpax.github.com/posts/2013-01-04-note-to-self.html
> On Sat, Jan 5, 2013 at 12:38 AM, Joey Adams <joeyadams3.14159 at gmail.com> wrote:
>> On Fri, Jan 4, 2013 at 4:43 PM, Janne Hellsten <jjhellst at gmail.com> wrote:
>>> I was just wondering if you have any past experience on multi-threaded
>>> use of SQLite? I hit some issues last week, started seeing
>>> SQLITE_BUSY on inserts and wasn't quite sure what to think about it.
>>> I wrote some notes about it here
>>> http://nurpax.github.com/posts/2013-01-04-note-to-self.html. Have you
>>> by any chance had to deal with such problems before?
>> According to the SQLite FAQ , only one writer can access the database at
>> a time. I haven't run into this myself, though.
>> Be careful with transactions. If you allow multiple threads to access a
>> database handle, and to issue BEGIN/COMMIT on their own terms, then one
>> thread might issue BEGIN and interfere with other transactions. Thus, make
>> sure the MVar lock is held for the duration of the transaction.
>> PS: Mind CCing this to database-devel at haskell.org ?
>> : http://www.sqlite.org/faq.html#q5
> database-devel mailing list
> database-devel at haskell.org
More information about the database-devel