The RENAME CONSTRAINT
statement changes the name of a constraint on a column.
The RENAME CONSTRAINT
statement performs a schema change. For more information about how online schema changes work in CockroachDB, see Online Schema Changes.
It is not possible to rename a constraint for a column referenced by a view. For more details, see View Dependencies.
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 | logon_pkey | 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 | logon_pkey | 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)