Re: how to generate a list of distinct scalar values from a column which type is array - Mailing list pgsql-sql

am  Wed, dem 21.02.2007, um 19:21:09 +0100 mailte Sergio Andreozzi folgendes:
> Dear all,
> 
> given a column which type is for instance varchar(20)[], is there any SQL
> command that let me generate the list of distinct scalar values?
> 
> 
> e.g.:
>              col1
> row 1: (aaa, bb, c)
> row 2: (dddd, eeee)
> row 3: (aaa, eeee)
> 
> the query should return:
> 
> aaa
> bb
> c
> dddd
> eeee
> 
> if not, I guess the approach is to use stored procedure. Any code snippet/
> suggestion?

You can, for each row, split the array into the elements with a loop
over array_lower, array_upper, returns this element. Yes, this is a
setof-function. Than you can do a simple select distinct * from
your_function.


I hope this may help you.


Andreas
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Andreas Kretschmer
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