I am designing a Microsoft Access database to store results from lab equipment. They are in the form of hundreds of lists of frequency vs. response curves which I have previously stored rather easily, but inefficiently in Excel.
The difficulty comes from the fact that the frequency can vary from 1 – 50E9 Hz, the step size between data points can vary from 1 – 1E9, Hz, and the number of points can vary from ~ 100 – 40,000. This has brought up a challenge when it comes to table design because everything I try seems to be very inefficient.
I have considered using links to external text files to store the data points which solves the table design, but seems to violate good database design. I’ve considered using tables of arrays (i.e. Start Freq, Stop Freq, Freq Step Size, and Array of Responses), but the array sizes could vary greatly which seems just as inefficient.
Is there a recommended practice for storing this type of data? It seems like a common task when storing instrument data, but I can’t seem to find anything in web searches. Any assistance will be greatly appreciated.
Looks like a classic 1:N relationship to me. “1” is the measurement session and “N” is all the measurements (i.e. data points) taken in that session. This is modeled by two tables and one foreign key between them, similar to this:
Tweak the fields to suit your needs, but this general design should be more than able to handle large amounts of data and varying numbers of measurements per session.
That being said, MS Access has historically had significant limitations on the size of the data that can be stored in a single database. If you hit these limits, consider using a “real” DBMS.