SSB(SQLservice Service Broker) 入门实例
前两天用了 MSsql里的 SSB委托机制,做了一个消息分发的小功能,在这里简单跟大家分享一下方法跟实例.
step 1:perpar database & data
use master go Create database Inventory go use Inventory go Create table inventory ( TitleId nvarchar(6) not null, Quantity int not null, primary key (TitleId,Quantity) ); go insert inventory values ('pc1001',100); insert inventory values ('pc1002',200); insert inventory values ('pc1003',300); insert inventory values ('pc1004',400);
step 2: 创建整个SSB的基础框架.
首先创建信息类型
Create Message Type [//mark/v10/types/inventory] Create Message Type [//mark/v10/types/inventoryresponse]
创建合约
create contract [//mark/v10/contracts/inventorycontract] ( [//mark/v10/types/inventory] sent by initiator, [//mark/v10/types/inventoryresponse] sent by target );
创建队列与服务
create queue [inventory client queue]; create service [//mark/v10/services/inventory client] on queue [inventory client queue] go --create inventory service create queue [inventory queue]; create service [//mark/v10/services/inventory] on queue [inventory queue] ( [//mark/v10/contracts/inventorycontract] );
step 3:发送消息到消息队列中
use Inventory go --send message begin transaction declare @dialog_id uniqueidentifier begin dialog conversation @dialog_id from service [//mark/v10/services/inventory client] to service '//mark/v10/services/inventory' on contract [//mark/v10/contracts/inventorycontract] with encryption = off; send on conversation @dialog_id message type [//mark/v10/types/inventory] ( '<InventoryUpdate> <TitleId>pc1001</TitleId> <Quantity>102</Quantity> </InventoryUpdate>' ); commit transaction;
发送成功后,可以查询 inventory_queue
select conversation_handle, cast(message_body as xml) as conversation_body from [Inventory queue]
这里只是查询了两列。
其中conversation_body 就是 我们发出的信息了。
setp 4: 从 inventory queue 中获取信息并更新数据
use inventory go begin transaction declare @dialog_id uniqueidentifier declare @message_body xml declare @amount int; declare @title nvarchar(128); receive @dialog_id = conversation_handle, @message_body = message_body from [dbo].[Inventory queue] print 'handle is' + cast(@dialog_id as nvarchar(90)) print 'message body is' + cast(@message_body as nvarchar(max) ) if(@dialog_id is not null) begin set @amount = @message_body.value('(/InventoryUpdate/Quantity)[1]','int'); set @title = @message_body.value('(/InventoryUpdate/TitleId)[1]','nvarchar(100)'); print 'a:'+cast(@amount as nvarchar(100)) print 'b:'+@title; Update inventory set Quantity = @amount where TitleId = @title; end end conversation @dialog_id; commit transaction;
操作成功后再去查询inventory queue的表 犹豫里面的数据已经被receive 出来 就为空了。
数据同时被更新了
step 5: 接下来做个自动监听功能,只要有信息发送到队列,相关队列,就可以自动执行功能.
首先建立个存储过程,(把receive 中的那段代码拿过来就可以了)
use Inventory go --create procedure to receive message and update table create proc InventoryProc as begin transaction declare @dialog_id uniqueidentifier declare @message_body xml declare @amount int; declare @title nvarchar(128); waitfor( receive @dialog_id = conversation_handle, @message_body = message_body from [dbo].[Inventory queue]),timeout 5000; print 'handle is' + cast(@dialog_id as nvarchar(90)) print 'message body is' + cast(@message_body as nvarchar(max) ) if(@dialog_id is not null) begin set @amount = @message_body.value('(/InventoryUpdate/Quantity)[1]','int'); set @title = @message_body.value('(/InventoryUpdate/TitleId)[1]','nvarchar(100)'); print 'a:'+cast(@amount as nvarchar(100)) print 'b:'+@title; Update inventory set Quantity = @amount where TitleId = @title; end end conversation @dialog_id; commit transaction; go
队列监听
alter queue [inventory queue] with activation( status = on, procedure_name= InventoryProc, max_queue_readers=2, execute as self ); go
完成后,只要发送队列信息后,就可以了
PS: 我们定义了 两个队列 还有个 inventory client queue
这个队列保存的是成功或者error 提示。用receive 方法也可以提取出来。
select message_type_name from [Inventory client queue]
以上的 message type service 等信息 如图所示,都在这里.
以上是SSB的入门实例,以后会再写一篇实际应用上的(以上的sql code 都是纯手工输入,可能还存在错误(虽然校验了两遍),如果发生错误,对不起大家了。)