Re: How to set array element to null value
On Mon, Jul 09, 2018 at 03:28:45PM +0530, Brahmam Eswar wrote: > I'm trying to reset array element to null. You can do this in SQL as follows: SELECT ARRAY( SELECT CASE e WHEN 'ABC' THEN NULL ELSE e FROM UNNEST(x) _(e) ) This should really be going to pgsql-general because to is about how to use PostgreSQL, not how to change PostgreSQL. Best, David. -- David Fetter http://fetter.org/ Phone: +1 415 235 3778 Remember to vote! Consider donating to Postgres: http://www.postgresql.org/about/donate
Re: How to set array element to null value
Brahmam Eswar schrieb am 09.07.2018 um 11:58: > I'm trying to reset array element to null. but 3rd line of below snippet is > giving the compilationĀ error. > > > FOR indx_1 IN array_lower(X, 1)..array_upper(X, 1) LOOP > IF X[indx_1].REFERENCE_VALUE = 'ABC' THEN > X[indx_1].REFERENCE_VALUE:=''; > END IF; > END LOOP; What data type is X exactly? It looks like a composite record type. (Also: an empty string '' is not the same as NULL)
Re: How to set array element to null value
2018-07-09 11:58 GMT+02:00 Brahmam Eswar : > I'm trying to reset array element to null. but 3rd line of below snippet > is giving the compilation error. > > > FOR indx_1 IN array_lower(X, 1)..array_upper(X, 1) LOOP > IF X[indx_1].REFERENCE_VALUE = 'ABC' THEN > X[indx_1].REFERENCE_VALUE:=''; > END IF; > END LOOP; > > a) plpgsql doesn't support complex expressions on left side of assign command, b) '' is not NULL in PostgreSQL you can write your code some like DECLARE r RECORD; BEGIN FOR i IN array_lower(x, 1) .. array_upper(x, 1) LOOP r := x[i]; IF r.reference_value = 'ABC' THEN r.reference_value := NULL; x[i] := r; END IF; END LOOP; END; Regards Pavel > -- > Thanks & Regards, > Brahmeswara Rao J. >
How to set array element to null value
I'm trying to reset array element to null. but 3rd line of below snippet is giving the compilation error. FOR indx_1 IN array_lower(X, 1)..array_upper(X, 1) LOOP IF X[indx_1].REFERENCE_VALUE = 'ABC' THEN X[indx_1].REFERENCE_VALUE:=''; END IF; END LOOP; -- Thanks & Regards, Brahmeswara Rao J.