Re: how to proccess record returning null

From: John R Pierce <pierce(at)hogranch(dot)com>
To: pgsql-bugs(at)postgresql(dot)org
Subject: Re: how to proccess record returning null
Date: 2012-09-14 21:56:22
Message-ID: 5053A806.4060700@hogranch.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-bugs

On 09/14/12 8:31 AM, te wrote:
> Sorry I didnt mention it.
>
> temp is a table name.
>
> FOR r in select distinct(id) from temp
>
> There are no distinct id's in table 'temp', so record 'r' has null values.
>
> So I guess the control is not going inside the loop.
>
> Any suggestions?

there's a difference between zero records, and a record containing null
fields..

yes, if there are no records, the loop will execute zero iterations, and
result will be integer zero.

as coded, for each record, it will test if id is null or an empty
string, the result value will be that of the last distinct(id);

since no id is likely to be null or an empty string, the odds are, it
will be returning 999 if there are any records and 0 if there aren't any.

what exactly do you WANT to do?

--
john r pierce N 37, W 122
santa cruz ca mid-left coast

In response to

Responses

Browse pgsql-bugs by date

  From Date Subject
Next Message Fujii Masao 2012-09-15 05:57:12 Re: [BUGS] BUG #7534: walreceiver takes long time to detect n/w breakdown
Previous Message Tom Lane 2012-09-14 16:45:35 Re: BUG #7539: Result mismatch on Postgres 9.2.0