Databases are valuable in measurement applications both to hold the measured results data, and to manage the items to be measured.
The key to successful database applications is:- Data modelling: careful choice of the content and arrangement of data tables
- Queries: effective use of queries reduces data before reports are formatted
In some applications the data for each part measured is very extensive, containing curves (e.g. s-parameter curves) or images of parts. In these applications, we use a two-tier approach: the test data are stored directly to disk, and only a file name and summary are stored in the database.
For small to medium-size applications, we typically use Microsoft Access. Microsoft Access has a non-standard language and interface but has the advantage of being widely used. For larger applications, we use preferentially an SQL server. Depending on the business need and technical environment, data is either fed directly to the SQL server from the measurement application, or written first to local disk and updated periodically to the SQL server.