Building UPDATE statements

If you need to update a given number of columns of a table without modifying others, you can follow the pattern given in this section.

How to do it...

1. You need two pieces of information to run an UPDATE statement:
   • The data to update: A common way of describing such information is to use pointers to represent updated values. Consider the following example:

     type UpdateUserRequest struct {
       Name *string
       LastLogin *time.Time
       AvatarURL *string
     }

   Here, a column will only be updated if the corresponding field is not null. For instance, with the following instance of UpdateUserRequest, only the LastLogin and AvatarURL fields will be updated:

   now:=time.Now()
   urlString:="https://example.org/avatar.jpg"
   update:=UpdateUserRequest {
     LastLogin: &now,
     AvatarURL: &urlString,
   }

   • The record locator: This is usually the unique identifier of the row that needs to be updated. However, it is also...