Search Postgresql Archives

Re: Inline count on a query

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

 



On Wednesday, August 19, 2020, Laura Smith <n5d9xq3ti233xiyif2vp@xxxxxxxxxxxxx> wrote:
Hi,

Let's say we've got a fairly basic table :

create table networks (
lan_id text not null,
net_id text not null,
port_id text not null
);
create index net_uniq on networks(lan_id,port_id);

The query conundrum I am facing is that I need to add metadata to the output of the query that indicates the count of ports a given net has on a lan.

So, for example, given :
insert into networks(lan_id,net_id,port_id) values('L1','N1,'P1');
insert into networks(lan_id,net_id,port_id) values('L1','N1,'P2');

The metadata count would be 1, 2 (because 'N1' has 'P1' and 'P2' on 'L1').

Is there a sensible way to query this without stressing out Postgres too much ?  I'm guessing a CTE of some sort ?


Suggest you provide your desired output in table format, and show “the query” that you mention.

David J.


[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