CREATE QUEUE v17

EDB Postgres Advanced Server includes extra syntax not offered by Oracle with the CREATE QUEUE SQL command. You can use this syntax with DBMS_AQADM.

Name

CREATE QUEUE — Create a queue.

Synopsis

Use CREATE QUEUE to define a new queue:

CREATE QUEUE <name> QUEUE TABLE <queue_table_name> [ ( { <option_name option_value>} [, ... ] ) ]

Where possible values for option_name and the corresponding option_value are:

TYPE [normal_queue | exception_queue]
RETRIES [INTEGER]
RETRYDELAY [DOUBLE PRECISION]
RETENTION [DOUBLE PRECISION]

Description

The CREATE QUEUE command allows a database superuser or any user with the system-defined aq_administrator_role privilege to create a queue in the current database.

If the name of the queue is schema-qualified, the queue is created in the specified schema. If the CREATE QUEUE command doesn't include a schema, the queue is created in the current schema. You can create a queue only in the schema where the queue table resides. The name of the queue must be unique among queues in the same schema.

Use DROP QUEUE to remove a queue.

Parameters

name

The name (optionally schema-qualified) of the queue to create.

queue_table_name

The name of the queue table with which this queue is associated.

option_name option_value

The name of any options to associate with the new queue and the corresponding value for the option. If the call to CREATE QUEUE includes duplicate option names, the server returns an error. The following values are accepted:

• TYPE — Specify normal_queue to indicate that the queue is a normal queue or exception_queue for an exception queue. An exception queue accepts only dequeue operations.
• RETRIES — An integer value that specifies the maximum number of attempts to remove a message from a queue.
• RETRYDELAY — A double-precision value that specifies the number of seconds after a rollback that the server waits before retrying a message.
• RETENTION — A double-precision value that specifies the number of seconds to save a message in the queue table after dequeueing.

Examples

This command creates a queue named work_order that's associated with a queue table named work_order_table:

CREATE QUEUE work_order QUEUE TABLE work_order_table (RETRIES 5, RETRYDELAY 2);

The server allows 5 attempts to remove a message from the queue and enforces a retry delay of 2 seconds between attempts.

See also

ALTER QUEUE, DROP QUEUE