Re: multiple statements.. and locking

#1

Benjamin <benjamin (AT) netyantra (DOT) com> writes:

Quote:

I have a C application. I have to modify a row in a table, n then
immediately access a field in that row.
These operation of modifying and accessing has to be atomic.So, i have
to lock the row.

The UPDATE in your example does that already; I think you should just
drop the LOCK ...

Quote:

BEGIN; LOCK TABLE tablename in ROW EXCLUSIVE MODE; UPDATE tablename set
colname=value WHERE rowprimary='a' ; SELECT b from tablename WHERE
rowprimary='a'; COMMIT;

regards, tom lane

---------------------------(end of broadcast)---------------------------
TIP 9: the planner will ignore your desire to choose an index scan if your
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Re: multiple statements.. and locking

comp.databases.postgresql.novice comp.databases.postgresql.novice

Re: multiple statements.. and locking - 04-05-2004 , 11:31 PM