Re: row level lock and table level locks

>TupleTables are just temporary data structures to hold transiently
>created tuples during execution of a query. There's usually one for
>each plan node.

So, if i have the following transaction:
begin work;
select * from students where a age=19 for update;
lock table studens in share mode;
commit;

The TupleTable will exist for the query from the point the query is made
untill the transaction is committed? or does the TupleTable go away as soon
as query is finished executing?
I would think the TupleTable for that query is held untill the transaction
is committed since lock on the tuple is endtill the end of transaction
Thanks

>From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
>To: "Jenny -" <nat_lazy(at)hotmail(dot)com>
>CC: pgsql-hackers(at)postgresql(dot)org
>Subject: Re: [HACKERS] row level lock and table level locks Date: Mon, 08
>Sep 2003 12:49:51 -0400
>
>"Jenny -" <nat_lazy(at)hotmail(dot)com> writes:
> > I found out that TupleTable stores per-tuple information(it stores
> > HeapTupleData) and that also there are multiple TupleTables in the db at
>a
> > time.Based on what are diffrent TupleTables created?
>
cc>
> regards, tom lane
>
>---------------------------(end of broadcast)---------------------------
>TIP 4: Don't 'kill -9' the postmaster

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