Thanks for the replay
I think you missed on second detail mail :
For more details:
I have two tables master,child.
with child having fk to master.
Now
that master table contains 4M rows . while I update them (Master table)
the inserts are going into waiting mode on child table.
Update
acquired row exclusive lock on master table , and the insert on child
table acquired access share and share lock,row share on master.
Is
this is what preventing for inserting records into child table, I mean
is the row exclusive lock conflicting with the locks insert(which is again row exclusive log) wants to
hold?
With Regards
Ashish...
--- On Wed, 9/1/08, Albe Laurenz <laurenz.albe@wien.gv.at> wrote:
From: Albe Laurenz <laurenz.albe@wien.gv.at>
Subject: Re: [GENERAL] Insert waiting for update?
To: ashish_postgre@yahoo.co.in, "pggeneral" <pgsql-general@postgresql.org>
Cc: ashish.karalkar@netcore.co.in
Date: Wednesday, 9 January, 2008, 8:53 PM
Ashish Karalkar wrote:
> I am having table with 4M rows.
> I am trying to update all these rows with statement
>
> update mytable set mycolumn=0;
>
> At the same time there are insert happening on the table.
> but all these insert are in waiting mode.
> does update is locking the table for insert?
>
> does insert and update confilict with each other?
Not normally, but
it can happen.
You could
SELECT l.locktype, t.relname, l.pid, l.transactionid, l.mode, l.granted
FROM pg_catalog.pg_locks l LEFT OUTER JOIN
pg_catalog.pg_class t ON l.relation = t.oid;
and
SELECT procpid, current_query FROM pg_stat_activity;
while the inserts hang. Maybe the result will indicate why.
Are there any triggers or rules defined?
What indexes are defined on the table?
Yours,
Laurenz Albe
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