Trouble Matching GraphQL Scalar to original data set

Question

I'm a graphQL newbie, and I'm confused about how to set up my schema correctly for train stations. I've set up my train station schema with all the relevant information (station id, station name, etc) corresponding to the train station data; all of this queries correctly.

The trouble is that my train station data has the number of train lines at any given station in an array. The individual trains do not have their own table to which they are joining; rather the train lines are just in an array.

Would it make sense to load all the data into a relational database rather than a series of objects? Should I create a custom scalar type to handle an array?