updating values in material master table

Hi,

I have a requirement where in which if the user wants to change the value of some fields of a particular record in the o/p,then he checks the checkbox of that record and click on the change button.Then the control goes to the update screen.There are many fields present in the update screen and also checkboxes were present beside each field.The user can change the values of the fields here and click on th execute button.Then only the checked field values should get updated in the material master table.

Can anyone tell me how only the checked field values can be updated in the material master table