| 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 | yes_or_no | 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; null
for all other data types. The maximum octet length depends on
the declared character maximum length (see above) and the
server encoding.
|
| character_set_catalog | sql_identifier | Applies to a feature not available in PostgreSQL |
| character_set_schema | sql_identifier | Applies to a feature not available in PostgreSQL |
| character_set_name | sql_identifier | Applies to a feature not available in PostgreSQL |
| collation_catalog | sql_identifier | Not yet implemented |
| collation_schema | sql_identifier | Not yet implemented |
| collation_name | sql_identifier | Not yet implemented |
| 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 can 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 can
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,
timestamp, or interval type, this column contains the (declared
or implicit) fractional seconds precision of the type for this
attribute, that is, the number of decimal digits maintained
following the decimal point in the seconds value. For all
other data types, this column is null.
|
| 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 | yes_or_no | Applies to a feature not available in PostgreSQL |