37.6. attributes

37.6. `attributes`
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37.6. `attributes`

+ The view attributes contains information about + the attributes of composite data types defined in the database. + (Note that the view does not give information about table columns, + which are sometimes called attributes in PostgreSQL contexts.) + Only those attributes are shown that the current user has access to (by way + of being the owner of or having some privilege on the type). +

Table 37.4. attributes Columns

+ Column Type + + + Description +
+ `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` + + + Name of the database containing the collation of the attribute + (always the current database), null if default or the data type + of the attribute is not collatable +
+ `collation_schema` `sql_identifier` + + + Name of the schema containing the collation of the attribute, + null if default or the data type of the attribute is not + collatable +
+ `collation_name` `sql_identifier` + + + Name of the collation of the attribute, null if default or the + data type of the attribute is not collatable +
+ `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` + + + If `data_type` identifies an interval type, + this column contains the specification which fields the + intervals include for this attribute, e.g., `YEAR TO + MONTH`, `DAY TO SECOND`, etc. If no + field restrictions were specified (that is, the interval + accepts all fields), and for all other data types, this field + is null. +
+ `interval_precision` `cardinal_number` + + + Applies to a feature not available + in PostgreSQL + (see `datetime_precision` for the fractional + seconds precision of interval type attributes) +
+ `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 +

+ Column Type +

+ Description +

+ 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 +

+ Name of the database containing the collation of the attribute + (always the current database), null if default or the data type + of the attribute is not collatable +

+ collation_schema sql_identifier +

+ Name of the schema containing the collation of the attribute, + null if default or the data type of the attribute is not + collatable +

+ collation_name sql_identifier +

+ Name of the collation of the attribute, null if default or the + data type of the attribute is not collatable +

+ 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 +

+ If data_type identifies an interval type, + this column contains the specification which fields the + intervals include for this attribute, e.g., YEAR TO + MONTH, DAY TO SECOND, etc. If no + field restrictions were specified (that is, the interval + accepts all fields), and for all other data types, this field + is null. +

+ interval_precision cardinal_number +

+ Applies to a feature not available + in PostgreSQL + (see datetime_precision for the fractional + seconds precision of interval type attributes) +

+ 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 +

+ See also under Section 37.17, a similarly + structured view, for further information on some of the columns. +

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37.5. `applicable_roles`	Home	37.7. `character_sets`