column-definition:

1 column-name
2? FOR
2.1! COLUMN
2.2 system-column-name
3 data-type
4+ 
4? 
4 default-clause
4.0! GENERATED ALWAYS
4.0?
4.0 GENERATED BY DEFAULT
4.1 (1) 

4.1? identity-options
4 datalink-options (2) 
4 NOT NULL
4 column-constraint
5 (3) 


data-type:

1 built-in-type
1 distinct-type-name