The built-in editing functionality of the Grid is beyond the described behavior but can be easily implemented.
Instead of using the Grid's built-in editing system, you can create your own.
For example, try using Templates Columns and in each cell, you can place a TextBox and a Button.
Using the button, you can make the Grid fire specific commands see How to Fire Command Events. For instance, buttons in the Column1 cells could fire "UpdateColumn1Data" and so, you can access the cell, its value and only update that value in the database. Here is the article that will help you access the cells and values: Accessing Values and Controls
You may also inspect the code in the following example to see how it was implemented and get some ideas, inspiration from it: Update all, individual or selected rows using RadGrid with InPlace edit mode
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