Save button clicked- but no changes in data

Question

All,
We have lots of forms. Some form spans multiple table in database and some form spans multiple rows in database like a list.
My question is what is the best practice for not changing modified_date on database - if nothing in record is changed.
For example in my form user changes only 1 row out of 30 rows displayed.
Currently we are updating all the 30 rows. So the date modified gets changed.
What is the best practice to update only 1 row.
I could create dirty field in each row and check if row is updated. But then if the user make changes and then re-type- it does not give accurate picture.
Thanks,
Jill

Answer 1

consider capturing the entire row value along with the primary key of all the records that are updated,perhaps on the onclick or onchange event,append it with a separator and then assign it to a hidden field.
Say .the form looks like:
Sr.No EmpNO. EmpName      Age      (Primary Key) 
1.          1               JACK       35        100
2.          2               JILL          20       200if record with key 100 i.e JACK is edited say the Emp Name is changed to MACK the hidden field will contain 1#MACK#100.For Multiple Entries Add Another Separator | for differentiating between records.
At the Java Side,split the string into array.
array[0]=1
array[2]=MACK
array[3]=100.
Now you have the updated values as well as the PID.
Just update the same.
Hope this helps ..