DROP SEQUENCE
The DROP SEQUENCE
statement removes a sequence from a database.
Note:
This statement performs a schema change. For more information about how online schema changes work in CockroachDB, see Online Schema Changes.
Required privileges
The user must have the DROP
privilege on the specified sequence(s).
Synopsis
Parameters
Parameter | Description |
---|---|
IF EXISTS | Drop the sequence only if it exists; if it does not exist, do not return an error. |
sequencename | The name of the sequence you want to drop. Find the sequence name with SHOW CREATE on the table that uses the sequence. |
RESTRICT | (Default)_ Do not drop the sequence if any objects (such as constraints and tables) use it. |
CASCADE | Not yet implemented. Currently, you can only drop a sequence if nothing depends on it. |
Examples
Remove a sequence (no dependencies)
In this example, other objects do not depend on the sequence being dropped.
> SELECT * FROM information_schema.sequences;
+------------------+-----------------+--------------------+-----------+-------------------+-------------------------+---------------+-------------+----------------------+---------------------+-----------+--------------+
| sequence_catalog | sequence_schema | sequence_name | data_type | numeric_precision | numeric_precision_radix | numeric_scale | start_value | minimum_value | maximum_value | increment | cycle_option |
+------------------+-----------------+--------------------+-----------+-------------------+-------------------------+---------------+-------------+----------------------+---------------------+-----------+--------------+
| def | db_2 | test_4 | INT | 64 | 2 | 0 | 1 | 1 | 9223372036854775807 | 1 | NO |
| def | test_db | customer_seq | INT | 64 | 2 | 0 | 101 | 1 | 9223372036854775807 | 2 | NO |
| def | test_db | desc_customer_list | INT | 64 | 2 | 0 | 1000 | -9223372036854775808 | -1 | -2 | NO |
| def | test_db | test_sequence3 | INT | 64 | 2 | 0 | 1 | 1 | 9223372036854775807 | 1 | NO |
+------------------+-----------------+--------------------+-----------+-------------------+-------------------------+---------------+-------------+----------------------+---------------------+-----------+--------------+
(4 rows)
> DROP SEQUENCE customer_seq;
DROP SEQUENCE
> SELECT * FROM information_schema.sequences
+------------------+-----------------+--------------------+-----------+-------------------+-------------------------+---------------+-------------+----------------------+---------------------+-----------+--------------+
| sequence_catalog | sequence_schema | sequence_name | data_type | numeric_precision | numeric_precision_radix | numeric_scale | start_value | minimum_value | maximum_value | increment | cycle_option |
+------------------+-----------------+--------------------+-----------+-------------------+-------------------------+---------------+-------------+----------------------+---------------------+-----------+--------------+
| def | db_2 | test_4 | INT | 64 | 2 | 0 | 1 | 1 | 9223372036854775807 | 1 | NO |
| def | test_db | desc_customer_list | INT | 64 | 2 | 0 | 1000 | -9223372036854775808 | -1 | -2 | NO |
| def | test_db | test_sequence3 | INT | 64 | 2 | 0 | 1 | 1 | 9223372036854775807 | 1 | NO |
+------------------+-----------------+--------------------+-----------+-------------------+-------------------------+---------------+-------------+----------------------+---------------------+-----------+--------------+
(4 rows)
See also
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