Is there a way to simulate VARCHAR2 datatype of other database systems?
You can emulate almost any database using domains. Varchars are a little bit tricky as they can have variable number of characters, but you can name your domains like that using quoted identifiers. Example:
CREATE DOMAIN "VARCHAR2(1)" AS VARCHAR(1);
Later, in table definition, you would use something like:
CREATE TABLE t1 (
As you can see, you must use quotes everywhere as '(' and ')' characters are reserved.