Обсуждение: Server does not reply to Alter Table
Using pgsql 7.1.3 I have found that on occasions, there is no reply to an
SQL statement like
ALTER TABLE x
ADD COLUMN y z
The table itself will be inaccessible for at least 10 minutes and/or error
messages will result. The column may or may not be added.
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Patrick Dunford, Christchurch, NZ
http://pdunford.godzone.net.nz/
http://www.trainweb.org/ferrymead/
Hi List , Could any one of you help me in finding out a way by which 1)when i login to postgres "begin transaction " command automatically executes . 2)i write commit it should commit as well as begin the new transaction . 3) similarly with rollback. from yogesh
"Yogesh Kansal" <yogesh@davlin.co.in> writes: > Hi List , > Could any one of you help me in finding out a way by which > 1)when i login to postgres "begin transaction " command automatically > executes . > 2)i write commit it should commit as well as begin the new transaction . > 3) similarly with rollback. Do it at the application level. -Doug -- Let us cross over the river, and rest under the shade of the trees. --T. J. Jackson, 1863
Patrick Dunford <dunfordsoft@clear.net.nz> writes:
> Using pgsql 7.1.3 I have found that on occasions, there is no reply to an
> SQL statement like
> ALTER TABLE x
> ADD COLUMN y z
You sure it's not just waiting for some other transaction to give up a
lock on the table? ALTER TABLE ADD COLUMN should be essentially
instantaneous, since it doesn't touch the table data. But it needs to
get exclusive lock on the table first.
regards, tom lane
no i want this while quering on the prompt of psql ... actually i want a precautionary measure while doing updates , inserts or delete to a table .. i want this so that i can roll back the whole transaction if i make some mistake .. thanks for reply. yogesh > "Yogesh Kansal" <yogesh@davlin.co.in> writes: > > > Hi List , > > Could any one of you help me in finding out a way by which > > 1)when i login to postgres "begin transaction " command automatically > > executes . > > 2)i write commit it should commit as well as begin the new transaction . > > 3) similarly with rollback. > > Do it at the application level. > > -Doug > -- > Let us cross over the river, and rest under the shade of the trees. > --T. J. Jackson, 1863 > -- Walking on water and developing software from a specification are easy if both are frozen." -- Edward V. Berard, "Life-Cycle Approaches"
"Yogesh Kansal" <yogesh@davlin.co.in> writes: > no i want this while quering on the prompt of psql ... actually i want a > precautionary measure while doing updates , inserts or delete to a table .. > i want this so that i can roll back the whole transaction if i make some > mistake .. Well, it can't be done without changing the code. So change the code, or live with it and remember to type BEGIN before you start working. -Doug -- Let us cross over the river, and rest under the shade of the trees. --T. J. Jackson, 1863
In article <25074.1012924704@sss.pgh.pa.us> in newsgroup comp.databases.postgresql.general on Tue, 5 Feb 2002 16:10:06 +0000 (UTC), Tom Lane(tgl@sss.pgh.pa.us) said... > Patrick Dunford <dunfordsoft@clear.net.nz> writes: > > Using pgsql 7.1.3 I have found that on occasions, there is no reply to an > > SQL statement like > > > ALTER TABLE x > > ADD COLUMN y z > > You sure it's not just waiting for some other transaction to give up a > lock on the table? ALTER TABLE ADD COLUMN should be essentially > instantaneous, since it doesn't touch the table data. But it needs to > get exclusive lock on the table first. Well if it doesn't send a message back to the client then there is no way of knowing this. I had it do the same thing on two Drop Table requests, eventually it came back and said the relation does not exist so I knew then it had dropped the table but not because it had replied to the first request.