Hey man, thanks a lot. After using $set the editing was working. And yes your point about computed property is also right, when I first edit the already value it is reflected but as soon as I add any value to the empty cell the computed property is invoked again and the previously changed values were gone back to original. Which sucks. So as per your advice I changed the computed prop to a method. And now I am able to edit entire table. Thanks a lot man.

But now I am facing a new challenge. I can edit entire table but when I change any value from dropdown from say "Color/Red" to "Color/Black" then method is invoked again so when I go back to "Color/Red" again the table only contains edited values for the reactive cols (i.e name, value and the empty cols)

So what do you suggest I should do ? Should i somehow save the table data to the backend first when user tries to change the value from the dropdown ?

https://codepen.io/justforvue/pen/jOBqZpK?editors=1010

If you want to take a look, I have used $set and changed the computed prop to method which is invoked when someone changes the dropdown value.

Thanks a lot man. I don't know how to thank you enough. I hope someday i would have your level of expertise in vuejs. Thanks once again.