Microsoft® SQL Server® 2012 Bible

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Chapter 25: Asynchronous Messaging with Service Broker

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WHERE name='HelloWorldMessage';

GO

--Query the sys.service_contracts catalog view

SELECT * FROM sys.service_contracts

WHERE name='HelloWorldContract'

GO

--Query the sys.service_queues_type catalog view

SELECT * FROM sys.service_queues

WHERE name in ('TargetQueue','InitiatorQueue');

GO

--Query the sys.services catalog view

SELECT * FROM sys.services

WHERE name in ('InitiatorService','TargetService');

GO

For a complete description of all Catalog Views available for Service Broker visit http://

msdn.microsoft.com/en-us/library/ms173780.aspx

Working with Dialogs

With the Service Broker infrastructure created, messages can be sent between services and

received from the queue. Messages exist as part of a conversation, and multiple conversa-

tions can be contained in a conversation group.

Service Broker makes multiple queue readers possible by locking the conversation group;

however, locking the conversation group with normal database commands is almost impos-

sible to accomplish effi ciently. Service Broker accordingly uses a new kind of database lock,

and only Service Broker commands understand this lock type.

Sending a Message to the Queue

The following code creates a conversation that is identifi ed by a conversationhandle

GUID. SEND places a single message onto a queue within a transaction. The BEGIN

CONVERSATION command opens the conversation, and the SEND command actually places

the message into the queue:

BEGIN TRANSACTION ;

DECLARE @message XML ;

SET @message = N'<message>Hello, World!</message>' ;

DECLARE @conversationHandle UNIQUEIDENTIFIER ;

BEGIN DIALOG CONVERSATION @conversationHandle

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