Declare variable from other variable - Mailing list pgsql-general

From Raul Kaubi
Subject Declare variable from other variable
Date
Msg-id CAO_+3-BRGqQXs4SNi8eaEyBNbzCODFVYJvDVJZBEDSQtA+68qg@mail.gmail.com
Whole thread Raw
Responses Re: Declare variable from other variable  (Yasin Sari <yasinsari81@googlemail.com>)
Re: Declare variable from other variable  (Thomas Kellerer <shammat@gmx.net>)
List pgsql-general
Hi

PostgreSQL 12.1

How can I declare another variable from another variable.
Basically from oracle, I can just: 
var1 := 'asda'||var2;

In postgres, I have the following example, I would like to use variable j to add number of months there.

" interval 'j month')::date; "

DO $$
DECLARE
v_var integer := 1;
v_from_date date;
BEGIN
for j in 0..v_var LOOP
v_from_date := (date_trunc('month',current_date) + interval 'j month')::date;
RAISE NOTICE '%', v_from_date;
END LOOP;
END;
$$ LANGUAGE plpgsql;

ERROR:  invalid input syntax for type interval: "j month"
LINE 1: ...LECT (date_trunc('month',current_date) + interval 'j month')... 


Raul 

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