Creating a row in a table with empty fields and saving the new data to DB after clicking save button

I m creating a Table in MII with the fields ID,NAME,AGE,SALARY with some data in that fields .Below the table i m taking ADD and SAVE buttons .

when i click Add button then a new row should be created with incrementing the ID number .

for example

if table has 3 rows then after clicking on the Add button then a row should be created with the id 4 and the fields should be empty.

After entering the data in the new row that is 4th row then after clicking on save button, the data should be saved in the data base.

I mean the new row which is created should allow the data which i type in the particular fields and later it should save after clicking save button.

please help me out to solve this issue.