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The SHOW CONSTRAINTS statement lists all named constraints as well as any unnamed CHECK constraints on a table.
Required privileges
The user must have any privilege on the target table.
Aliases
SHOW CONSTRAINT is an alias for SHOW CONSTRAINTS.
Synopsis
Parameters
| Parameter | Description |
|---|---|
table_name |
The name of the table for which to show constraints. |
Response
The following fields are returned for each constraint.
| Field | Description |
|---|---|
table_name |
The name of the table. |
constraint_name |
The name of the constraint. |
constraint_type |
The type of constraint. |
details |
The definition of the constraint, including the column(s) to which it applies. |
validated |
Whether values in the column(s) match the constraint. |
Example
> CREATE TABLE orders (
id INT PRIMARY KEY,
date TIMESTAMP NOT NULL,
priority INT DEFAULT 1,
customer_id INT UNIQUE,
status STRING DEFAULT 'open',
CHECK (priority BETWEEN 1 AND 5),
CHECK (status in ('open', 'in progress', 'done', 'cancelled')),
FAMILY (id, date, priority, customer_id, status)
);
> SHOW CONSTRAINTS FROM orders;
+------------+------------------------+-----------------+--------------------------------------------------------------------------+-----------+
| table_name | constraint_name | constraint_type | details | validated |
+------------+------------------------+-----------------+--------------------------------------------------------------------------+-----------+
| orders | check_priority | CHECK | CHECK (priority BETWEEN 1 AND 5) | true |
| orders | check_status | CHECK | CHECK (status IN ('open':::STRING, 'in progress':::STRING, | true |
| | | | 'done':::STRING, 'cancelled':::STRING)) | |
| orders | orders_customer_id_key | UNIQUE | UNIQUE (customer_id ASC) | true |
| orders | primary | PRIMARY KEY | PRIMARY KEY (id ASC) | true |
+------------+------------------------+-----------------+--------------------------------------------------------------------------+-----------+
(4 rows)
