Is there a pattern, which allows mapping the following datastructure to table columns?
The clue is, that there are 2 attributes, which depend on each other, one should be entered, when the other was entered - so mapping them to table columns is not satisfying, because then it is suggested to enter one datum without the other.
If both latitude and longitude are necessary, or both are to be left blank, then the coordinates pair should be treated as a single field.
The column header should designate the pair, like "coordinates".
When the coordinates cell gets focused, it should change its appearance to look like a coordinates pair input, with the two sets of degrees, minutes ans seconds, and the N/S or E/W choices.
Once the user has entered acceptable data (here is where you enforce the rule) and exited the coordinates field, then display the data in the cell normally as in any map or geolocation writing.
Notice that there are two suggestions combined here:
These are clearly geographic co-ordinates. Without knowing more about the function of your application:
Your row pair is used to input geographic co-ordinates: do you have users who will know how to decompose geographic co-ordinates and input them raw into a form like this without knowing that describing a location requires two of them? (I had a look at another of your questions, which I assume is a higher-fidelity mock-up of this question? If you are assigning different IDs to latitude and longitudes, how do you relate them?)
Depending on the rest of your interface design, you could do it several other ways:
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Additionally, I would strongly recommend not putting the last unit " outside the text box. It's strange, because it implies that the value of the entire cell is to be expressed in ", rather than that it applies only to the last segment of the value. (That is, unless this is an accepted standard in Germany.)
I think that there are few people who are comfortable with entering coordinates like these at all. While you can make entering them an option, I would not make it the first or only way of displaying and entering them. As an alternative, considder allowing users to point out locations on a map. Most users are familiar with interfaces like Google Maps, so navigating a map should be relatively straightforward for them.
