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The SHOW CONSTRAINTS statement lists all named constraints as well as any unnamed Check constraints on a table.
Warning:
The SHOW CONSTRAINTS statement is under development; the exact output will continue to change.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.
Warning:
The SHOW CONSTRAINTS statement is under development; the exact output will continue to change.| Field | Description |
|---|---|
Table |
The name of the table. |
Name |
The name of the constraint. |
Type |
The type of constraint. |
Column(s) |
The columns to which the constraint applies. For Check constraints, column information will be in Details and this field will be NULL. |
Details |
The conditions for a Check 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 | Type | Column(s) | Details |
+--------+------------------------+-------------+---------------+--------------------------------------------------------+
| orders | | CHECK | NULL | status IN ('open', 'in progress', 'done', 'cancelled') |
| orders | | CHECK | NULL | priority BETWEEN 1 AND 5 |
| orders | orders_customer_id_key | UNIQUE | [customer_id] | NULL |
| orders | primary | PRIMARY KEY | [id] | NULL |
+--------+------------------------+-------------+---------------+--------------------------------------------------------+
(4 rows)
