CREATE TABLE table_name (
id_col1 BIGINT GENERATED ALWAYS AS IDENTITY,
id_col2 BIGINT GENERATED ALWAYS AS IDENTITY (START WITH -1 INCREMENT BY 1),
id_col3 BIGINT GENERATED BY DEFAULT AS IDENTITY,
id_col4 BIGINT GENERATED BY DEFAULT AS IDENTITY (START WITH -1 INCREMENT BY 1)
)

This is the only way you can create an identity column in sparkSQL for delta lake table.