Creating a Nonpersistent Queue

Figure 9-7 Use Case Diagram: Creating a Nonpersistent Queue

Text description of the illustration adq09qad12.gif

To refer to the table of all basic operations having to do with the Administrative Interface see: "Use Case Model: Administrative Interface -- Basic Operations"

Purpose

Create a nonpersistent queue.

Usage Notes

The queue may be either single-consumer or multiconsumer queue. All queue names must be unique within a schema. The queues are created in a 8.1 compatible system-created queue table (AQ$_MEM_SC or AQ$_MEM_MC) in the same schema as that specified by the queue name. If the queue name does not specify a schema name, the queue is created in the login user's schema. Once a queue is created with CREATE_NP_QUEUE, it can be enabled by calling START_QUEUE. By default, the queue is created with both enqueue and dequeue disabled.

You can enqueue RAW and Object Type (ADT) messages into a nonpersistent queue. You cannot dequeue from a nonpersistent queue. The only way to retrieve a message from a nonpersistent queue is by using the OCI notification mechanism (see Registering for Notification).

You cannot invoke the listen call on a nonpersistent queue (see Listening to One (Many) Queue(s)).

Syntax

See Chapter 3, "AQ Programmatic Environments" for a list of available functions in each programmatic environment. Use the following syntax references for each programmatic environment:

• PL/SQL (DBMS_AQADM Package): Oracle9i Supplied PL/SQL Packages and Types Reference DBMS_AQADM, CREATE_NP_QUEUE procedure

• Visual Basic (OO4O): There is no applicable syntax reference for this use case

• Java (JDBC): There is no applicable syntax reference for this use case

Examples

See Chapter 3, "AQ Programmatic Environments" for a list of available functions in each programmatic environment. Examples are provided in the following programmatic environments.

• PL/SQL (DBMS_AQADM Package): Dropping a Queue Table

• VB (OO4O): Example not provided.

• Java (JDBC): Dropping a Queue Table

PL/SQL (DBMS_AQADM): Creating a Nonpersistent Queue

/* Create a nonpersistent single-consumer queue (Note: this is not preceded by
   creation of a queue table) */ 
EXECUTE dbms_aqadm.create_np_queue( 
   Queue_name           => 'Singleconsumersmsg_npque',  
   Multiple_consumers   => FALSE);  
 
/* Create a nonpersistent multi-consumer queue (Note: this is not preceded by
   creation of a queue table) */ 
EXECUTE dbms_aqadm.create_np_queue( 
   Queue_name           => 'Multiconsumersmsg_npque',  
   Multiple_consumers   => TRUE); 

Java (JDBC): Creating a Nonpersistent Queue

Feature not available through Java API.