Re: Any limitation in size for return result from SELECT?

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От Stephan Szabo
Тема Re: Any limitation in size for return result from SELECT?
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Msg-id 20030301190150.E21955-100000@megazone23.bigpanda.com
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Ответ на Any limitation in size for return result from SELECT?  ("Natasa Bulatovic" <n.bulatovic@zim.mpg.de>)
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On Tue, 25 Feb 2003, Natasa Bulatovic wrote:

> Select statement returns as a result concatenated all varchar, text
> and char columns of a table as one single column ...
>
> select col1||col2||col3||.....||col100 from table
>
> However, when the number of concatenated columns is bigger than 22 no
> result is given back (tested in psql, as well as from pgplsql)....

>
> Most of these columns for the test data are NULL...Datatypes of
> columns are mixed text, varchar, char...Select statement does not
> return any error...Just returns a row with a null result.... Any quick
> suggestions would be very useful....

Anything concatenated with a NULL is NULL.  You'll probably want to use
COALESCE(col1,'')||... for each of the columns that can be null.




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