Thread: Defining string to represent null values in select

Defining string to represent null values in select

From
Brent Wood
Date:
Hi,

I can specify the text used to represent a null value in output from copy, but I'd like to do something similar is
selectoutput, eg: all NULL values are represented by NA or NaN. 

I can't find anything in the docs about this.

This could be managed using case statements around all the columns in the query, but is there a simpler way, like
settinga system variable to specify this? 

Thanks,

  Brent Wood

Re: Defining string to represent null values in select

From
Andreas Kretschmer
Date:
Brent Wood <pcreso@yahoo.com> schrieb:

>
> Hi,
>
> I can specify the text used to represent a null value in output from copy, but I'd like to do something similar is
selectoutput, eg: all NULL values are represented by NA or NaN. 

COALESCE:
test=*# select coalesce(NULL, 'NaN');
 coalesce
----------
 NaN



Andreas
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