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InformationSchemaColumn interface

The view columns contains information about all table columns (or view columns) in the database. System columns (ctid, etc.) are not included. Only those columns are shown that the current user has access to (by way of being the owner or having some privilege).

Signature:

interface InformationSchemaColumn

Properties

Property	Modifiers	Type	Description
character_maximum_length		number | null	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		number | null	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		string | null	Applies to a feature not available in PostgreSQL
character_set_name		string | null	Applies to a feature not available in PostgreSQL
character_set_schema		string | null	Applies to a feature not available in PostgreSQL
collation_catalog		string | null	Name of the database containing the collation of the column (always the current database), null if default or the data type of the column is not collatable
collation_name		string | null	Name of the collation of the column, null if default or the data type of the column is not collatable
collation_schema		string | null	Name of the schema containing the collation of the column, null if default or the data type of the column is not collatable
column_default		any	Default expression of the column
column_name		string	Name of the column
data_type		string	Data type of the column, 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 udt_name and associated columns). If the column is based on a domain, this column refers to the type underlying the domain (and the domain is identified in domain_name and associated columns).
datetime_precision		number | null	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 column, 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.
domain_catalog		string | null	If the column has a domain type, the name of the database that the domain is defined in (always the current database), else null.
domain_name		string | null	If the column has a domain type, the name of the domain, else null.
domain_schema		string | null	If the column has a domain type, the name of the schema that the domain is defined in, else null.
dtd_identifier		string	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.)
generation_expression		any	If the column is a generated column, then the generation expression, else null.
identity_cycle		string	If the column is an identity column, then YES if the internal sequence cycles or NO if it does not; otherwise null.
identity_generation		"ALWAYS" | "BY DEFAULT" | null	If the column is an identity column, then ALWAYS or BY DEFAULT, reflecting the definition of the column.
identity_increment		string | null	If the column is an identity column, then the increment of the internal sequence, else null.
identity_maximum		string | null	If the column is an identity column, then the maximum value of the internal sequence, else null.
identity_minimum		string | null	If the column is an identity column, then the minimum value of the internal sequence, else null.
identity_start		string | null	If the column is an identity column, then the start value of the internal sequence, else null.
interval_precision		number | null	Applies to a feature not available in PostgreSQL (see datetime_precision for the fractional seconds precision of interval type columns)
interval_type		string | null	If data_type identifies an interval type, this column contains the specification which fields the intervals include for this column, 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.
is_generated		"ALWAYS" | "NEVER"	If the column is a generated column, then ALWAYS, else NEVER.
is_identity		YesNo	If the column is an identity column, then YES, else NO.
is_nullable		YesNo	YES if the column is possibly nullable, NO if it is known not nullable. A not-null constraint is one way a column can be known not nullable, but there can be others.
is_self_referencing		YesNo	Applies to a feature not available in PostgreSQL
is_updatable		YesNo	YES if the column is updatable, NO if not (Columns in base tables are always updatable, columns in views not necessarily)
maximum_cardinality		null	Always null, because arrays always have unlimited maximum cardinality in PostgreSQL
numeric_precision_radix		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_precision		number | null	If data_type identifies a numeric type, this column contains the (declared or implicit) precision of the type for this column. 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_scale		number | null	If data_type identifies an exact numeric type, this column contains the (declared or implicit) scale of the type for this column. 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.
ordinal_position		number	Ordinal position of the column within the table (count starts at 1)
scope_catalog		string | null	Applies to a feature not available in PostgreSQL
scope_name		string | null	Applies to a feature not available in PostgreSQL
scope_schema		string | null	Applies to a feature not available in PostgreSQL
table_catalog		string	Name of the database containing the table (always the current database)
table_name		string	Name of the table
table_schema		string	Name of the schema containing the table
udt_catalog		string	Name of the database that the column data type (the underlying type of the domain, if applicable) is defined in (always the current database)
udt_name		string	Name of the column data type (the underlying type of the domain, if applicable)
udt_schema		string	Name of the schema that the column data type (the underlying type of the domain, if applicable) is defined in