Обсуждение: PSQLODBC and TRANSACTIONS

Hi,

I'm trying transactions using M$-access and PSQLODBC without success,
Seems that backend locks itself
by opening two connections to work on the same table.

I have a table with 3 rows:

codice    nome        cap
---------------------------
1    pippo        0
2    pluto        0
3    topolino    0
---------------------------

I tryed to update table as:

UPDATE operatori SET cap = 1;

This works, but the next...

UPDATE operatori SET cap = 2;

At this point the backend was locked and I had to break connection...

(See attached log file)

Thanks for any help.

-Jose'-

Jose' Soares wrote:

> Hi,
>
> I'm trying transactions using M$-access and PSQLODBC without success,
> Seems that backend locks itself
> by opening two connections to work on the same table.
>
> I have a table with 3 rows:
>
> codice  nome            cap
> ---------------------------
> 1       pippo           0
> 2       pluto           0
> 3       topolino        0
> ---------------------------
>

The logfile shows that Access is using Manual Commit.   The last two lines show a separate connection
being made and then a select statement on "operatori" table.  But it is still locked from the other
connection.  (see below)

I don't think there is anything the driver can do about this.  You need Vladim's new locking code!   I
think that is going to be in the next version of Postgres.

Byron

<Highlights from the logfile>
BEGIN
UPDATE "operatori" SET "cap"='1' WHERE "codice" = '1  '
SELECT "codice","cap"  FROM "operatori"  WHERE "codice" = '3  '
UPDATE "operatori" SET "cap"='1' WHERE "codice" = '3  '
SELECT "codice","cap"  FROM "operatori"  WHERE "codice" = '2  '
UPDATE "operatori" SET "cap"='1' WHERE "codice" = '2  '

<Another connection is created here>

SQLDriverConnect(out)='DSN=PostgreSQL;DATABASE=hygea;SERVER=verde;PORT=5432;UID=marco;PWD=;READONLY=0;PROTOCOL=6.4;FAKEOIDINDEX=0;SHOWOIDCOLUMN=0;ROWVERSIONING=0;SHOWSYSTEMTABLES=0;CONNSETTINGS=set+ksqo+to+%27on%27%3b'

<This one hangs it>
SELECT "operatori"."codice" FROM "operatori"

Hello Byron,

martedì, 12 gennaio 99, you wrote:



BN> Jose' Soares wrote:

>> Hi,
>>
>> I'm trying transactions using M$-access and PSQLODBC without success,
>> Seems that backend locks itself
>> by opening two connections to work on the same table.
>>
>> I have a table with 3 rows:
>>
>> codice  nome            cap
>> ---------------------------
>> 1       pippo           0
>> 2       pluto           0
>> 3       topolino        0
>> ---------------------------
>>

BN> The logfile shows that Access is using Manual Commit.   The last two lines show a separate connection
BN> being made and then a select statement on "operatori" table.  But it is still locked from the other
BN> connection.  (see below)

BN> I don't think there is anything the driver can do about this.  You need Vladim's new locking code!   I
BN> think that is going to be in the next version of Postgres.

BN> Byron

BN> <Highlights from the logfile>
BN> BEGIN
BN> UPDATE "operatori" SET "cap"='1' WHERE "codice" = '1  '
BN> SELECT "codice","cap"  FROM "operatori"  WHERE "codice" = '3  '
BN> UPDATE "operatori" SET "cap"='1' WHERE "codice" = '3  '
BN> SELECT "codice","cap"  FROM "operatori"  WHERE "codice" = '2  '
BN> UPDATE "operatori" SET "cap"='1' WHERE "codice" = '2  '

BN> <Another connection is created here>
BN>
SQLDriverConnect(out)='DSN=PostgreSQL;DATABASE=hygea;SERVER=verde;PORT=5432;UID=marco;PWD=;READONLY=0;PROTOCOL=6.4;FAKEOIDINDEX=0;SHOWOIDCOLUMN=0;ROWVERSIONING=0;SHOWSYSTEMTABLES=0;CONNSETTINGS=set+ksqo+to+%27on%27%3b'

BN> <This one hangs it>
BN> SELECT "operatori"."codice" FROM "operatori"

Thank you for reply Byron.

I hope that v6.5 may solve my problem.

-Jose'-