36.32. key_column_usage
Last updated
Last updated
The view key_column_usage
identifies all columns in the current database that are restricted by some unique, primary key, or foreign key constraint. Check constraints are not included in this view. Only those columns are shown that the current user has access to, by way of being the owner or having some privilege.
Table 36.30. key_column_usage
Columns
Name
Data Type
Description
constraint_catalog
sql_identifier
Name of the database that contains the constraint (always the current database)
constraint_schema
sql_identifier
Name of the schema that contains the constraint
constraint_name
sql_identifier
Name of the constraint
table_catalog
sql_identifier
Name of the database that contains the table that contains the column that is restricted by this constraint (always the current database)
table_schema
sql_identifier
Name of the schema that contains the table that contains the column that is restricted by this constraint
table_name
sql_identifier
Name of the table that contains the column that is restricted by this constraint
column_name
sql_identifier
Name of the column that is restricted by this constraint
ordinal_position
cardinal_number
Ordinal position of the column within the constraint key (count starts at 1)
position_in_unique_constraint
cardinal_number
For a foreign-key constraint, ordinal position of the referenced column within its unique constraint (count starts at 1); otherwise null