Skip site navigation (1) Skip section navigation (2)

SQL syntax I've been unable to figure out....

From: Karl Denninger <karl(at)denninger(dot)net>
To: pgsql-sql(at)postgresql(dot)org
Subject: SQL syntax I've been unable to figure out....
Date: 2008-12-25 19:35:08
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-sql
for the following

Assuming a table containing:

name text
address text
uri text

I wish to run a query that will return those rows where:

("name" is not null) AND (distinct) (uri is the same for two or more 
entries AND name is different between the two entries))

Example data:

george who 1
sam where 2
sam what 2
[null] why 2
leroy never 2


sam 2
leroy 2

I haven't been able to concoct an SQL query that will filter out the 
"double entry" for sam (I only want one of them) but will return those 
cases where more than one name has a given URI in the table.

I can do it programmatically (e.g. from "C" selecting the table ordered 
by URIs, distinct by name) and then stepping through by hand, but can't 
figure out a single SQL statement that will accomplish this.

Thanks in advance

Karl Denninger

Attachment: karl.vcf
Description: text/x-vcard (124 bytes)


pgsql-sql by date

Next:From: Rodrigo E. De León PlicetDate: 2008-12-25 21:04:32
Subject: Re: SQL syntax I've been unable to figure out....
Previous:From: Hilco WijbengaDate: 2008-12-25 07:54:57
Subject: Re: How to improve PgSql Performance using npgsql

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group