Search Postgresql Archives

Re: Secret Santa List

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




Why not generate the required results in a SELECT then update from that. row_number() could allow you to generate a random number to each giver, then we can generate another random number and join to each random number. That'll give you a giver and recipient combination.

e.g:

select giver,recipient from
(select row_number() over (order by random()) rn, giver from secretsanta) g
inner join
(select row_number() over (order by random()) rn, giver recipient from secretsanta) r on g.rn = r.rn

You can then wrap that up in a CTE, something along the lines of:

with cte (giver, recipient) as (
select giver,recipient from
(select row_number() over (order by random()) rn, giver from secretsanta) g
inner join
(select row_number() over (order by random()) rn, giver recipient from secretsanta) r on g.rn = r.rn
)
update secretsanta set recipient = cte.recipient from cte WHERE cte.giver = secretsanta.giver;

Hey, I think that works!  Thanks!




--
Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general



[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Postgresql Jobs]     [Postgresql Admin]     [Postgresql Performance]     [Linux Clusters]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Postgresql & PHP]     [Yosemite]
  Powered by Linux