Implementing 'UPDATE SET CASE WHEN ELSE' with column reference in ELSE in SeaORM

[M4n5ter]

I am working with SeaORM and attempting to perform an UPDATE SET CASE WHEN ELSE operation where I need the ELSE part to reference a column instead of a static value. However, I am having trouble expressing this with the current API.

Normally, in SQL, we can write something like this:

UPDATE my_table
SET
    c1 = CASE
            WHEN id = 'record1' THEN new_value_for_c1
            ELSE c1
         END,
    c2 = CASE
            WHEN id = 'record2' THEN new_value_for_c2
            ELSE c2
         END,
    c3 = CASE
            WHEN id = 'record3' THEN new_value_for_c3
            ELSE c3
         END
WHERE id IN ('record1', 'record2', 'record3');

In SeaORM, I can't figure out how to express it.