问题描述
我正在尝试通过ODP.NET通过服务从oracle AQ中出消息
我有两个条件
-
队列中记录表中要出队的
- MessageID将由 服务
- 一旦服务出队消息提示该记录对其他服务实例不可用,则意味着该记录应被锁定,直到事务提交或事务到期为止
问题:
我的队列就像
BEGIN DBMS_AQADM.CREATE_QUEUE_TABLE(
Queue_table => '"DEVENV1_CUSTOM"."INTEGRATION_MSG_QUEUE"',Queue_payload_type => '"DEVENV1_CUSTOM"."TRIGGER_AUDIT_TYPE"',Sort_list => 'ENQ_TIME',Compatible => '10.0.0',primary_instance => 3,secondary_instance => 2);
END;
有人可以建议我一种方法来传递要从队列中出队的记录msgid,以及如何锁定它们以防止他人访问它直到提交或超时。
public static void DequeueMessage(string MessageID)
{
// Create connection
string constr = "my constring";
Oracle.DataAccess.Client.OracleConnection con = new Oracle.DataAccess.Client.OracleConnection(constr);
// Create queue
OracleAQQueue queue = new OracleAQQueue("DEVENV1_CUSTOM.INTEGRATION_MSG_QUEUE_Q",con);
try
{
// Open connection
con.open();
// Begin txn for enqueue
Oracle.DataAccess.Client.OracleTransaction txn = con.BeginTransaction();
// Prepare to Dequeue
queue.DequeueOptions.Visibility = OracleAQVisibilityMode.OnCommit;
queue.DequeueOptions.Wait = 10;
queue.DequeueOptions.DequeueMode = OracleAQDequeueMode.Locked;
// Set message type for the queue
queue.MessageType = OracleAQMessageType.Udt;
queue.UdtTypeName = "TRIGGER_AUDIT_TYPE";
queue.DequeueOptions.MessageId = System.Text.Encoding.ASCII.GetBytes ("A0CB9F328889420D8F0C8A62BF38B454");
// Dequeue message
OracleAQMessage deqMsg = queue.Dequeue();
TRIGGER_AUDIT_TYPE data = (TRIGGER_AUDIT_TYPE)deqMsg.Payload;
// Dequeue txn commit
txn.Commit();
}
catch (Exception e)
{
Console.WriteLine("Error: {0}",e.Message);
}
finally
{
// Close/dispose objects
con.Close();
con.dispose();
}
}
解决方法
问题在于,Oracle返回的字节数组与.net创建的字节数组不同(如果插入,请阅读Little Endian和Big Endian的内容)
所以我通过直接从oracle转换数组并将其用于出队的方式解决了这个问题
OracleCommand oracleCommand = new OracleCommand("Select MSGID from INTEGRATION_MSG_QUEUE where msgid='B85439241C9241A4A6B1869F08F382E7'",con);
var K= oracleCommand.ExecuteScalar();
Byte[] rawBytesFromOracle =K as byte[];
// Begin txn for enqueue
Oracle.DataAccess.Client.OracleTransaction txn = con.BeginTransaction();
// Prepare to Dequeue
queue.DequeueOptions.Visibility = OracleAQVisibilityMode.OnCommit;
queue.DequeueOptions.Wait = 10;
queue.DequeueOptions.DequeueMode = OracleAQDequeueMode.Locked;
queue.DequeueOptions.MessageId = rawBytesFromOracle;
// Set message type for the queue
queue.MessageType = OracleAQMessageType.Udt;
queue.UdtTypeName = "TRIGGER_AUDIT_TYPE";
Console.WriteLine("DeQueueing ............ ");
// Dequeue message
OracleAQMessage deqMsg = queue.Dequeue();
TRIGGER_AUDIT_TYPE data = (TRIGGER_AUDIT_TYPE)deqMsg.Payload;
Console.WriteLine("Dequeued message...." + data.CMESSAGEBODY );