Table Structure and Update Schedule
While a transaction date or timestamp is frequently a good choice for the partitioning column, other choices present themselves for consideration for other categories of workloads and data. Consider a table with detailed information about telephone calls maintained by a telecommunications company. This table stores rows that contain the originating telephone number, a timestamp for the beginning of the call, and the duration of the call, among other things, for each outgoing call. Rows are retained for a variable length of time, but rarely for more than six weeks. Retention is based on the call date and the monthly bill preparation date. The primary index is a composite of the telephone number and the call-start timestamp. This column set implies that the index was chosen to provide good distribution, not to facilitate data access, and also that the likelihood of any direct primary index joins is remote.