+= Operator - SQL Server to PostgreSQL Migration

In SQL Server, the += operator adds or concatenates value to the variable. In PostgreSQL, you have to use var := var + value for numbers, and var := var || value for strings.

SQL Server:

  DECLARE @var INT = 1;
  DECLARE @str VARCHAR(30) = 'a';
 
  -- For numbers += works as addition
  SET @var += 3;
  -- For strings += works as concatenation
  SET @str += 'b';
 
  SELECT @var, @str;
  #  4  ab

PostgreSQL:

  DO $$
  DECLARE
    var INT = 1;
    str VARCHAR(30) = 'a';
  BEGIN
    var := var + 3;
    str := str || 'b';
 
    RAISE NOTICE ' % %', var, str;
  END $$;

For more information, see SQL Server to PostgreSQL Migration.