pg_range
The catalog pg_range
stores information about range types. This is in addition to the types' entries in pg_type
.
Table 52.42. pg_range
Columns
Name | Type | References | Description |
---|---|---|---|
rngtypid |
oid |
|
OID of the range type |
rngsubtype |
oid |
|
OID of the element type (subtype) of this range type |
rngcollation |
oid |
|
OID of the collation used for range comparisons, or 0 if none |
rngsubopc |
oid |
|
OID of the subtype's operator class used for range comparisons |
rngcanonical |
regproc |
|
OID of the function to convert a range value into canonical form, or 0 if none |
rngsubdiff |
regproc |
|
OID of the function to return the difference between two element values as double precision , or 0 if none |
rngsubopc
(plus rngcollation
, if the element type is collatable) determines the sort ordering used by the range type. rngcanonical
is used when the element type is discrete. rngsubdiff
is optional but should be supplied to improve performance of GiST indexes on the range type.