Database representation of JSOC data series

[This is a modified version of what I wrote for Jim's CDRL document, so it repeats (and probably somtimes contradicts) some of what has been said above. It uses a different example than the one in section 2.5]

The data making up the records and units of a data series specified in a JSD are represented in the JSOC by a collection of database tables and records, as well as files and directories on disk and/or tape. The information in the JSD in stored in a number of global tables, while the data representing the values of keywords and links for each data record are stored in a single database table specific to the series. Finally, the data representing the data segments of a record are stored in files on disk or tape, managed by the SUMS. In the following we describe the details of these tables.