update from select join code example

Example 1: update with join

UPDATE
        first_table ft
        JOIN second_table st ON st.some_id = ft.some_id
        JOIN third_table tt  ON tt.some_id = st.some_id
        .....
    SET
        ft.some_column = some_value
    WHERE ft.some_column = 123456 AND st.some_column = 123456

Example 2: update from select join

UPDATE t1
SET t1.COL1 = t2.COL1, t1.COL2 = t2.COL2
FROM my_table AS t1
JOIN my_other_table AS t2 ON t1.COLID = t2.ID
WHERE t1.COL3 = 'OK';