> I have a table that i use to store session > > Table Session > ID: VARCHAR(16); /* GUID ID */ > Expiry_date: Timestamp; > Data: Varchar(1000); > > i use the table like this only : > > Insert into Session(ID,Expiry_date,Data) > VALUES (CHAR_TO_UUID(NewGUID), NOW + 15minutes,...) > > Update Session Set > data=... > Expiry_date= NOW + 15minutes > where > id=... and > Date_expired< 'NOW' > > Select ... from SESSION where > ID=... and Expiry_date> 'NOW' > > THat ok, > > now the probleme is that i have another thread that one time a day delete all > the expired node > > Delete From SESSION where Expiry_date< NOW - 3 days
How many records approx.? > i use isc_tpb_write + isc_tpb_read_committed + isc_tpb_no_rec_version + > isc_tpb_wait for this second thread (but normally as i delete the rec that > expire 3 days ago they must not be any probleme of deadlock) > > but the probleme is that this SQL make hours (days?) to return :( > if i replace the isc_tpb_wait by isc_tpb_nowait then i have often some > deadlock (why ?? still not understand ...) By using isc_tpb_no_rec_version you basically disable Firebird's MVCC capabilities, so you explicitly tell Firebird to not use the back-record version mechansim when changing/deleting data. This beams you back into the good old days of MS SQL Server 2000 in read/write scenarios. ;-) Additionally, you also might take garbage collection into account for both, record data and index entries. You may inspect MON$RECORD_STATS for getting some counters on if garbage collection is performed. The Trace API gives you that information per executed statement as well ... -- With regards, Thomas Steinmaurer (^TS^) Firebird Technology Evangelist http://www.upscene.com/ Do you care about the future of Firebird? Join the Firebird Foundation: http://www.firebirdsql.org/en/firebird-foundation/ > ------------------------------------ > > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > > Visit http://www.firebirdsql.org and click the Resources item > on the main (top) menu. Try Knowledgebase and FAQ links ! > > Also search the knowledgebases at http://www.ibphoenix.com > > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > Yahoo! Groups Links > > >
