Deletion/record visibility error in PG with Python...

[Durumdara]

Hi!

PGSQL makes me crazy...

I port my apps to PGSQL, and I near to finish - but I got this problem...

Params: PGSQL 8.3, Windows, Pylons, PGDB, DBUTILS...

I opened the connection with DBUTILS. I have one thread (the test thread),
possible it have more in the background, I don't know...

See this pseudocode:

start trs ("rollback; begin;")
delete old recs
insert new recs
commit

I delete all of old records with:
"delete from levelfo where level = :level"

This I do in one transaction that protect the next sequences to.

Later I want to insert the records, BUT:

        def GetCodes(reks):
            l = []
            for rek in reks:
                l.append(str(rek['KOD']))
            return str(l)
        def LogInsertedReks(Index):
            csql = "select * from levelfo where level=%d" %
self.LevelRek['KOD']
            self.Cur.execute(csql)
            reks = dwdb.FetchAll(self.Cur)
            self.log.info(Index + ' #### INSERTED REKS ####')
            self.log.info('%s' % GetCodes(reks))

        for levelforek in self.LevelFoReks:
            LogInsertedReks('Start1')
            LogInsertedReks('Start2')
            LogInsertedReks('Start3')
            LogInsertedReks('Start4')
            LogInsertedReks('Start5')
            LogInsertedReks('Start6')
            kod = levelforek['KOD']
            self.log.info('#### INSERT ####')
            self.log.info('%s' % levelforek['KOD'])
            LogInsertedReks('Start7')
            LogInsertedReks('Start8')
            LogInsertedReks('Start9')

See this log:
18:07:02,276 INFO  [xxx] Start1 #### INSERTED REKS ####
18:07:02,276 INFO  [xxx] []
18:07:02,292 INFO  [xxx] Start2 #### INSERTED REKS ####
18:07:02,292 INFO  [xxx] []
18:07:02,292 INFO  [xxx] Start3 #### INSERTED REKS ####
18:07:02,292 INFO  [xxx] []
18:07:02,306 INFO  [xxx] Start4 #### INSERTED REKS ####
18:07:02,306 INFO  [xxx] []
18:07:02,306 INFO  [xxx] Start5 #### INSERTED REKS ####
18:07:02,306 INFO  [xxx] []
18:07:02,306 INFO  [xxx] Start6 #### INSERTED REKS ####
18:07:02,306 INFO  [xxx] []
18:07:02,306 INFO  [xxx] #### INSERT ####
18:07:02,306 INFO  [xxx] 11551
18:07:02,306 INFO  [xxx] Start7 #### INSERTED REKS ####
18:07:02,306 INFO  [xxx] []
18:07:02,619 INFO  [xxx] Start8 #### INSERTED REKS ####
18:07:02,619 INFO  [xxx] ['11555', '11556', '11557', '11558']
18:07:02,634 INFO  [xxx] Start9 #### INSERTED REKS ####
18:07:02,634 INFO  [xxx] ['11555', '11556', '11557', '11558']
18:07:02,697 INFO  [xxx] After UID #### INSERTED REKS ####
18:07:02,697 INFO  [xxx] ['11555', '11556', '11557', '11558']

As you see, I don't do anything (like db operations), and deleted records
are appearing...
Hmmmm... possible is it a cursor changing?

When I change my logger to see the object ids, I can see the cursor changing
(in the background):

18:21:29,134 INFO  [xxx] Start7 #### INSERTED REKS ####
18:21:29,134 INFO  [xxx] []
18:21:29,134 INFO  [xxx] Start7 #### CURSOR INFO ####
18:21:29,134 INFO  [xxx] [<DBUtils.SteadyDB.SteadyDBCursor instance at
0x01955710>]
18:21:29,134 INFO  [xxx] [<DBUtils.SteadyDB.SteadyDBConnection instance at
0x019555A8>]
********** 18:21:29,134 INFO  [xxx] [<pgdb.pgdbCursor instance at
0x019556E8>]
18:21:29,431 INFO  [xxx] Start8 #### INSERTED REKS ####
18:21:29,431 INFO  [xxx] ['11555', '11556', '11557', '11558']
18:21:29,431 INFO  [xxx] Start8 #### CURSOR INFO ####
18:21:29,431 INFO  [xxx] [<DBUtils.SteadyDB.SteadyDBCursor instance at
0x01955710>]
18:21:29,431 INFO  [xxx] [<DBUtils.SteadyDB.SteadyDBConnection instance at
0x019555A8>]
********** 18:21:29,431 INFO  [xxx] [<pgdb.pgdbCursor instance at
0x0195AE18>]

What happened? How I can avoid the cursor changing? How to fix it in my
transaction?
I never ask for new cursor, I used same variable in all of my context
(self.Cur)... :-(

So what is the solution? Drop DBUtils? Or what?

Thanks for your help:
    dd
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