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Actually TDMS is quite robust. I'm not saying you can't break it, but I had a few tests where multiple references were opened and closed in parallel, and reading and writing took place in an uncontrolled way, and there wasn't any data lost on the writes. This suggests to me that there is a central driver that all API calls go into which handles the reading and writing. This isn't to say data loss can't happen in odd cases of multiple reads/writes in parallel. These cases should be avoided. I just wanted to mention that in my experience it is quite robust. The TDMS read has an offset and range for performing a read. So you can graph a subset of the data without having to read all of it. But for something like decimate you will likely need to read all values of the range you want, and then decimate it in LabVIEW, which is likely less memory efficient than a database call that has that built into the select statement. Also getting something like a Min or Max in TDMS can be less efficient than a database call, if you have open ended queries. By that I mean if you know you want to have the min and max of all channels, then when you are performing the writing of those channels, you can also write properties of the channel that is the min and max. Then when you are reading the file these properties are already written in the file and can be read without having to read every data point. These are sorta like queries where the result is written in the file, knowing that you may want to look for them later. For queries you know you'll want to do this is great, but if you don't know what you are going to want to look for in a post-processing way, then you will need to read all values, and calculate the result. For me each channel, and each sample has a Pass or Fail associated with it, and I want to know if a test passed in every cycle, meaning that every sample of the channel was a pass. Instead of reading every sample, I just write a single Pass or Fail property on the entire channel. If that is Pass then I know every sample of that test passed. I can also combine this and look at if every test has this passed property, and if it does then write a Pass property on the entire file. Then I just need to read this one property to know if the entire file passed. I knew I would want this query like information available, so I wrote it into the program that writes the TDMS files. If I now wanted to know every time a sample was above 0.5, I would have to write custom code to read every sample and get the results, because that isn't a property I wrote into the application.