-- Demo: references rules (RF01, RF02, RF04, RF05, RF06)
SELECT
    missing_tbl.column_a
FROM
    my_table;
-- RF01: reference to object not present in FROM

SELECT
    column_a
FROM
    my_table AS a
JOIN
    other_table AS b ON a.id = b.ref_id;
-- RF02: unqualified column with multiple referenced tables

SELECT
    sum.a
FROM
    my_table AS sum;
-- RF04: keyword used as identifier (alias)

SELECT
    "my-column"
FROM
    my_table;
-- RF05: special characters in identifier

SELECT
    "SIMPLE_COL"
FROM
    my_table;
-- RF06: unnecessary quoted identifier