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STAR Databases: Navigation
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Offline computing tutorial | Maintained by Jeff Porter |
Last modified Fri Jul 03 00:19:00 1998 |
Consistent use of all STAR database data requires that the
various data have a well understood navigation scheme. This scheme
relies on references by run-number, event-number, time-stamp, &
version-names. The general picture of how these data are tied
together is shown below. Not all databases are depicted (e.g.
Geometry) but the basic access keys between database types are
indicated. See also the descriptions below for, |
TimeStamp The TimeStamp that is stored both on the DAQ Raw data files and in the Database is the standard unix timestamp (unsigned int). The value is relative to the date, 1969-12-31 19:00:00 (unix-time=0), and has a unique range up to the date, 2037-12-31 23:59:59 (unix-time=2145934799). MySQL has a storage type called Date-Time for which the storage is unix-time while the display is done in the ascii string format noted here,
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Version Name The Version Name is a 128 char string (127+'\0') that identifies a particular version of data instances apart from any default version. In short, it is one of the primary keys associated with the lookup of database data. For example, two calls (below) prepare data for store (or request) the C++ API,
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Run & Event Number
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Servers & DataBases
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