| udt_catalog | sql_identifier | Name of the database containing the data type (always the current database) |
| udt_schema | sql_identifier | Name of the schema containing the data type |
| udt_name | sql_identifier | Name of the data type |
| attribute_name | sql_identifier | Name of the attribute |
| ordinal_position | cardinal_number | Ordinal position of the attribute within the data type (count starts at 1) |
| attribute_default | character_data | Default expression of the attribute |
| is_nullable | character_data | YES if the attribute is possibly nullable,
NO if it is known not nullable.
|
| data_type | character_data | Data type of the attribute, if it is a built-in type, or
ARRAY if it is some array (in that case, see
the view element_types), else
USER-DEFINED (in that case, the type is
identified in attribute_udt_name and
associated columns).
|
| character_maximum_length | cardinal_number | If data_type identifies a character or bit
string type, the declared maximum length; null for all other
data types or if no maximum length was declared.
|
| character_octet_length | cardinal_number | If data_type identifies a character type,
the maximum possible length in octets (bytes) of a datum (this
should not be of concern to
PostgreSQL users); null for all
other data types.
|
| numeric_precision | cardinal_number | If data_type identifies a numeric type, this
column contains the (declared or implicit) precision of the
type for this attribute. The precision indicates the number of
significant digits. It may be expressed in decimal (base 10)
or binary (base 2) terms, as specified in the column
numeric_precision_radix. For all other data
types, this column is null.
|
| numeric_precision_radix | cardinal_number | If data_type identifies a numeric type, this
column indicates in which base the values in the columns
numeric_precision and
numeric_scale are expressed. The value is
either 2 or 10. For all other data types, this column is null.
|
| numeric_scale | cardinal_number | If data_type identifies an exact numeric
type, this column contains the (declared or implicit) scale of
the type for this attribute. The scale indicates the number of
significant digits to the right of the decimal point. It may
be expressed in decimal (base 10) or binary (base 2) terms, as
specified in the column
numeric_precision_radix. For all other data
types, this column is null.
|
| datetime_precision | cardinal_number | If data_type identifies a date, time, or
interval type, the declared precision; null for all other data
types or if no precision was declared.
|
| interval_type | character_data | Not yet implemented |
| interval_precision | character_data | Not yet implemented |
| attribute_udt_catalog | sql_identifier | Name of the database that the attribute data type is defined in
(always the current database)
|
| attribute_udt_schema | sql_identifier | Name of the schema that the attribute data type is defined in
|
| attribute_udt_name | sql_identifier | Name of the attribute data type
|
| scope_catalog | sql_identifier | Applies to a feature not available in PostgreSQL |
| scope_schema | sql_identifier | Applies to a feature not available in PostgreSQL |
| scope_name | sql_identifier | Applies to a feature not available in PostgreSQL |
| maximum_cardinality | cardinal_number | Always null, because arrays always have unlimited maximum cardinality in PostgreSQL |
| dtd_identifier | sql_identifier | An identifier of the data type descriptor of the column, unique
among the data type descriptors pertaining to the table. This
is mainly useful for joining with other instances of such
identifiers. (The specific format of the identifier is not
defined and not guaranteed to remain the same in future
versions.)
|
| is_derived_reference_attribute | character_data | Applies to a feature not available in PostgreSQL |