# 36.51. table\_constraints

The view `table_constraints` contains all constraints belonging to tables that the current user owns or has some privilege other than `SELECT` on.

#### **Table 36.49. `table_constraints` 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 (always the current database)      |
| `table_schema`       | `sql_identifier` | Name of the schema that contains the table                                      |
| `table_name`         | `sql_identifier` | Name of the table                                                               |
| `constraint_type`    | `character_data` | Type of the constraint: `CHECK`, `FOREIGN KEY`, `PRIMARY KEY`, or `UNIQUE`      |
| `is_deferrable`      | `yes_or_no`      | `YES` if the constraint is deferrable, `NO` if not                              |
| `initially_deferred` | `yes_or_no`      | `YES` if the constraint is deferrable and initially deferred, `NO` if not       |
| `enforced`           | `yes_or_no`      | Applies to a feature not available in PostgreSQL (currently always `YES`)       |


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