The relational database and calibration software for the Caltech millimeter array

A relational database management system has been implemented on the Caltech millimeter-wave array for both real-time astronomical engineering data and post-processing calibration and analysis. This system provides high storage-efficiency for the data and on-line access to data from multiple observing seasons. The ability to access easily the full database enables more accurate calibration of the raw data and greatly facilitates the calibration process. In this article we describe both the structure of the mm-array database and the implementation of a data analysis program, both of which make extensive use of Sybase, a commercial database management system with application development software. This use of relational database technology in real-time astronomical data storage and calibration may serve as a prototype for similar systems at other observatories.