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 37.16. constraint_column_usage Columns
| Column Type Description | 
|---|
| 
 Name of the database that contains the table that contains the column that is used by some constraint (always the current database) | 
| 
 Name of the schema that contains the table that contains the column that is used by some constraint | 
| 
 Name of the table that contains the column that is used by some constraint | 
| 
 Name of the column that is used by some constraint | 
| 
 Name of the database that contains the constraint (always the current database) | 
| 
 Name of the schema that contains the constraint | 
| 
 Name of the constraint | 
If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.