On Tue, 2003-11-18 at 08:54, Alex wrote:
> Hi,
>
> i have a problem with quoting in plpgsql. I try to insert dynamically
> some conditions into a select statment but for some reason it does not work.
>
> condition := '' AND price > 500 '';
>
> SELECT INTO tmpRec * WHERE xxxxxx || condition || ORDER BY userId ;
> What is the correct way to do this ?
FOR tmpRec IN EXECUTE ''SELECT INTO tmpRec * WHERE xxxxxx '' ||
condition || '' ORDER BY userId'' LOOP
...statements...
END LOOP;
From the manual:
37.6.4. Executing Dynamic Commands
Oftentimes you will want to generate dynamic commands inside
your PL/pgSQL functions, that is, commands that will involve
different tables or different data types each time they are
executed. PL/pgSQL's normal attempts to cache plans for commands
will not work in such scenarios. To handle this sort of problem,
the EXECUTE statement is provided:
EXECUTE command-string;
where command-string is an expression yielding a string (of type
text) containing the command to be executed. This string is fed
literally to the SQL engine.
Note in particular that no substitution of PL/pgSQL variables is
done on the command string. The values of variables must be
inserted in the command string as it is constructed.
--
Oliver Elphick Oliver.Elphick@lfix.co.uk
Isle of Wight, UK http://www.lfix.co.uk/oliver
GPG: 1024D/3E1D0C1C: CA12 09E0 E8D5 8870 5839 932A 614D 4C34 3E1D 0C1C
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thy name, O most High." Psalms 92:1
