Range Types
8.17. Range Types
Range types are data types representing a range of values of some element type (called the range's subtype). For instance, ranges of timestamp
might be used to represent the ranges of time that a meeting room is reserved. In this case the data type is tsrange
(short for "timestamp range"), and timestamp
is the subtype. The subtype must have a total order so that it is well-defined whether element values are within, before, or after a range of values.
Range types are useful because they represent many element values in a single range value, and because concepts such as overlapping ranges can be expressed clearly. The use of time and date ranges for scheduling purposes is the clearest example; but price ranges, measurement ranges from an instrument, and so forth can also be useful.