PG_RANGE
PG_RANGE records information about range types, except for records of types in PG_TYPE.
| Name | Type | Reference | Description |
|---|---|---|---|
| rngtypid | oid | oid in PG_TYPE | OID of the range type |
| rngcollation | oid | oid in PG_COLLATION | OID of the collation used for range comparisons (0 if none) |
| rngsubopc | oid | oid in PG_OPCLASS | OID of the subtype's operator class used for range comparisons |
| rngcanonical | regproc | proname in PG_PROC | Name of the function to convert a range value into canonical form (0 if none) |
| rngsubdiff | regproc | proname in PG_PROC | Name of the function used to calculate the difference between two elements in a range. The return value of the function is of the double-precision type. If the function does not exist, the value of rngsubdiff is 0. |
rngsubopc determines the sort ordering used by the range type. rngcanonical is used when the element type is discrete.
