---
title: "`constraint_table_usage`"
id: infoschema-constraint-table-usage
pg_version: "20devel"
---

<a id="infoschema-constraint-table-usage"></a>

## 35.19. `constraint_table_usage`

The view `constraint_table_usage` identifies all tables in the current database that are used by some constraint and are owned by a currently enabled role. (This is different from the view `table_constraints`, which identifies all table constraints along with the table they are defined on.) For a foreign key constraint, this view identifies the table that the foreign key references. For a unique or primary key constraint, this view simply identifies the table the constraint belongs to. Check constraints and not-null constraints are not included in this view. 

**constraint_table_usage Columns**

| Column Type | Description | 
| --- | --- |
| `table_catalog` `sql_identifier` | Name of the database that contains the table that is used by some constraint (always the current database) |
| `table_schema` `sql_identifier` | Name of the schema that contains the table that is used by some constraint |
| `table_name` `sql_identifier` | Name of the table 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 |