sum multiple rows in postgresql code example

Example 1: postgresql insert multiple rows

INSERT INTO table_name (column_list)
VALUES
    (value_list_1),
    (value_list_2),
    ...
    (value_list_n);

Example 2: sum of multiple columns in postgres

SELECT 
   Val1,
   Val2,
   Val3,
   sum(Val1 + Val2 + Val3) as 'Total'
FROM Emp