CONSTRAINT_TABLE_USAGE
Applies to: 
Databricks SQL Databricks Runtime 11.3 LTS and above Unity Catalog only
Important
This feature is in Public Preview.
INFORMATION_SCHEMA.CONSTRAINT_TABLE_USAGE lists all constraints that reference a table as either a foreign or primary key within the catalog.
The rows returned are limited to the tables the user is privileged to interact with.
Definition
The CONSTRAINT_TABLE_USAGE relation contains the following columns:
| Name | Data type | Nullable | Standard | Description |
|---|---|---|---|---|
TABLE_CATALOG |
STRING |
No | Yes | Catalog containing the relation. |
TABLE_SCHEMA |
STRING |
No | Yes | Schema containing the relation. |
TABLE_NAME |
STRING |
No | Yes | Name of the relation. |
CONSTRAINT_CATALOG |
STRING |
No | Yes | Catalog containing the constraint. |
CONSTRAINT_SCHEMA |
STRING |
No | Yes | Schema containing the constraint. |
CONSTRAINT_NAME |
STRING |
No | Yes | Name of the constraint. |
Constraints
The following constraints apply to the CONSTRAINT_TABLE_USAGE relation:
| Class | Name | Column List | Description |
|---|---|---|---|
| Primary key | CON_TAB_USG_PK |
TABLE_CATALOG, TABLE_SCHEMA, TABLE_NAME, CONSTRAINT_CATALOG, CONSTRAINT_SCHEMA, CONSTRAINT_NAME |
Uniquely identifies the relation. |
| Foreign key | CON_TAB_USG_TABLES_FK |
TABLE_CATALOG, TABLE_SCHEMA, TABLE_NAME |
References TABLES |
| Foreign key | CON_TAB_USG_TAB_CONS_FK |
CONSTRAINT_CATALOG, CONSTRAINT_SCHEMA, CONSTRAINT_NAME |
References TABLE_CONSTRAINTS. |
Examples
> SELECT constraint_name
FROM information_schema.constraint_table_usage
WHERE table_schema = 'information_schema'
AND table_name = 'tables'