One testing can be database value is correctly showing up on the UI screen. Also the reverse say I do some transaction on the UI which will create some flag in the database. So we need to query the database to see if the flag is set properly. For example for one scenario a checkbox will be disabled on the screen and in the database for a particular field the flag will be false for this. You can query the database to see if the flag is correctly set or not.
Format should fit whatever standards your company is using, I don't think there is one format that covers everything. So long as you have all the information necessary to perform the case, that could be considered sufficient.
Cool added other things that you should look at as well, but it all depends on how your data is going to be used. The integrity of the data is one thing, but if its then used in Views or copied to other tables or utilzed in reports, then those should always work properly.