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The RENAME CONSTRAINT statement changes the name of a constraint on a column.
Note:
It is not possible to rename a constraint for a column referenced by a view. For more details, see View Dependencies.
Tip:
This command can be combined with other ALTER TABLE commands in a single statement. For a list of commands that can be combined, see ALTER TABLE. For a demonstration, see Add and rename columns atomically.
Synopsis
Required privileges
The user must have the CREATE privilege on the table.
Parameters
| Parameter | Description |
|---|---|
IF EXISTS | Rename the constraint only if a constraint of current_name exists; if one does not exist, do not return an error. |
table_name | The name of the table with the constraint you want to rename. |
current_name | The current name of the constraint. |
name | The new name you want to use for the constraint, which must be unique to its table and follow these identifier rules. |
Viewing schema changes
This schema change statement is registered as a job. You can view long-running jobs with SHOW JOBS.
Example
Rename a constraint
> CREATE TABLE logon ( login_id INT PRIMARY KEY, customer_id INT NOT NULL, sales_id INT, UNIQUE (customer_id, sales_id) ); > SHOW CONSTRAINTS FROM logon; table_name | constraint_name | constraint_type | details | validated +------------+--------------------------------+-----------------+----------------------------------------+-----------+ logon | logon_customer_id_sales_id_key | UNIQUE | UNIQUE (customer_id ASC, sales_id ASC) | true logon | primary | PRIMARY KEY | PRIMARY KEY (login_id ASC) | true (2 rows) > ALTER TABLE logon RENAME CONSTRAINT logon_customer_id_sales_id_key TO unique_customer_id_sales_id; > SHOW CONSTRAINTS FROM logon; table_name | constraint_name | constraint_type | details | validated +------------+-----------------------------+-----------------+----------------------------------------+-----------+ logon | primary | PRIMARY KEY | PRIMARY KEY (login_id ASC) | true logon | unique_customer_id_sales_id | UNIQUE | UNIQUE (customer_id ASC, sales_id ASC) | true (2 rows)