constraint_column_usageThe view constraint_column_usage identifies all columns in the current database that are used by some constraint. Only those columns are shown that are contained in a table owned by a currently enabled role. For a check constraint, this view identifies the columns that are used in the check expression. For a foreign key constraint, this view identifies the columns that the foreign key references. For a unique or primary key constraint, this view identifies the constrained columns.
Table 36.15. constraint_column_usage Columns
| Name | Data Type | Description |
|---|---|---|
table_catalog |
sql_identifier |
Name of the database that contains the table that contains the column that is used by some constraint (always the current database) |
table_schema |
sql_identifier |
Name of the schema that contains the table that contains the column that is used by some constraint |
table_name |
sql_identifier |
Name of the table that contains the column that is used by some constraint |
column_name |
sql_identifier |
Name of the column that is used by some constraint |
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 |