How do you identify the 'first 5 rows' of a table?
Do you have any specific records to be inserted into the table OR you just want some random 5 rows from another table?
If you want specific rows then you can use a 'where' clause in your select query. Otherwise, you may have to write something like:
INSERT INTO ERT_TY
FROM TRAIN12.DEPT where condition UNION ALL
FROM TRAIN12.DEPT where condition;
Repeat the Select query 5 times with Union All. So, there will be 5 select queries and each query should return one row to be added. I don't see if you can actually insert a fixed number of rows through a Select query in a single shot.