From: | "Bobus" <roblocke(at)gmail(dot)com> |
---|---|
To: | pgsql-sql(at)postgresql(dot)org |
Subject: | fetching unique pins in a high-transaction environment... |
Date: | 2006-10-29 16:36:48 |
Message-ID: | 1162139808.031657.23340@f16g2000cwb.googlegroups.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-sql |
Hi,
I posted this question to the "general" forum, but then discovered this
one which I think is more appropriate. Apologies for the cross-post.
We are in the process of porting an application from SQL Server to
PostgresQL.
We have a table which contains a bunch of prepaid PINs. What is the
best way to fetch the next available unique pin from the table in a
high-traffic environment with lots of concurrent requests?
For example, our PINs table might look like this and contain thousands
of records. (FYI, the PIN numbers are generated by a third party and
loaded into the table):
ID PIN USED_BY DATE_USED
....
100 1864678198
101 7862517189
102 6356178381
....
10 users request a pin at the same time. What is the easiest/best way
to ensure that the 10 users will get 10 unique pins, while eliminating
any waiting?
SQL Server supports the notion of a SELECT FOR UPDATE with a READPAST
hint which tells SQL Server to skip over locked rows instead of waiting
until the lock is lifted. This guarantees a unique pin will be
acquired every time without hampering performance.
Is there any equivalent in Postgres?
Any help would be greatly appreciated...
From | Date | Subject | |
---|---|---|---|
Next Message | Michael Fuhr | 2006-10-29 17:10:55 | Re: not able to execute query on spatial database. |
Previous Message | Jon Horsman | 2006-10-28 15:18:52 | Re: How to query information schema from shell script |