The scenario is to modify the records of a form, modify the multiple-selected items, and then save them. One way is to compare the modified selections with the pre-modified selections by the front-end itself, and determine which items are added and which items are deleted. , respectively passed to the background. One approach is that the front end always passes the currently selected item to the background every time it is modified, regardless of what it was before modification, and the background overwrites and updates it. Since I don’t understand the logic behind the scenes, I would like to ask you what your usual practices are like? What kind of plan is more reasonable?