Re: [GCSQL] DatabaseError: 0: Connection is already in use

Yes, that makes sense. It pops up in a finally clause of a
try/except/finally block, which was meant to ensure tables are
unlocked in the event of other DB snafus. I guess if the snafu is a
deadline exception, I never see it because the finally gets executed
(and this error pops up) before the Deadline Exceeded is re-raised.

Thanks. This still sucks, but at least I have a better understanding
of why. Darn deadlines... :-)

Jake



On Mon, Jun 25, 2012 at 7:32 PM, Ken Ashcraft <kash@google.com> wrote:
> This error typically happens when you have a deadline exceeded exception.
>  The app gives up, but the query is still running on the server.  If you try
> to do anything else with the connection, the server will complain that the
> connection is already in use.  So if you get the "connection already in use"
> error, it means that you probably have some place else in your code where
> you ignored the deadline exceeded exception and reused a connection.
>
> On Sat, Jun 23, 2012 at 5:47 AM, Jake Czyz <jjc.work@gmail.com> wrote:
>>
>> Hi Ken,
>>
>> Thanks, but could you please clarify?  Do you mean I need to catch
>> this error, recreate a connection and retry the same query?
>>
>> Jake
>>
>>
>>
>> On Fri, Jun 22, 2012 at 4:15 PM, Ken Ashcraft <kash@google.com> wrote:
>> > It means that the query is still executing on the server.  You need to
>> > throw
>> > away the connection and create a new one.
>> >
>> >
>> > On Fri, Jun 22, 2012 at 1:48 AM, Jake Czyz <jjc.work@gmail.com> wrote:
>> >>
>> >> Hello,
>> >>
>> >> My GAE app gets the following error occasionally during GC-SQL calls,
>> >> when unlocking previously locked tables.  Searching for the error
>> >> turned up nothing.  Does anyone have an idea about what could cause
>> >> it?
>> >>
>> >> <snip>
>> >>    cursor.execute('UNLOCK TABLES') #always unlock
>> >>  File "/base/python27_runtime/
>> >> python27_lib/versions/1/google/storage/speckle/python/api/rdbms.py",
>> >> line 424, in execute
>> >>    self._DoExec(request)
>> >>  File
>> >>
>> >> "/base/python27_runtime/python27_lib/versions/1/google/storage/speckle/python/api/rdbms.py",
>> >> line 355, in _DoExec
>> >>    response = self._conn.MakeRequest('Exec', request)
>> >>  File
>> >>
>> >> "/base/python27_runtime/python27_lib/versions/1/google/storage/speckle/python/api/rdbms.py",
>> >> line 711, in MakeRequest
>> >>    response = self._MakeRetriableRequest(stub_method, request)
>> >>  File
>> >>
>> >> "/base/python27_runtime/python27_lib/versions/1/google/storage/speckle/python/api/rdbms.py",
>> >> line 742, in _MakeRetriableRequest
>> >>    sql_exception.message))
>> >> DatabaseError: 0: Connection is already in use.
>> >>
>> >>
>> >> Thanks in advance,
>> >> Jake
>> >
>> >
>
>