SqlDependency 简单选择查询始终返回“无效”

本文关键字:无效 返回 简单选择 查询 SqlDependency | 更新日期: 2023-09-27 18:31:39

我正在尝试让 SqlDependency 对象给我通知,但到目前为止我无法让它工作。

我发送的 sql 查询是这样的:

SELECT [SocialMedia].[dbo].[Items].[Id]
  FROM [SocialMedia].[dbo].[Items]

我已经尝试过不带大括号,具有完全限定的名称,只有变量名称以及介于两者之间的所有内容。

Id 属于 Guid 类型,我没有在创建通知查询一文中看到任何提及它们不适用于 SqlDependency 对象

我还尝试发送多列以查看是否有效。

  SELECT SocialMedia.dbo.Items.Id, 
         SocialMedia.dbo.Items.DateTimeCreated, 
         SocialMedia.dbo.Items.AuthorId
  FROM   SocialMedia.dbo.Items

那也行不通。


这是我的表 SQL:

USE [SocialMedia]
SET ANSI_NULLS ON
SET QUOTED_IDENTIFIER ON
SET ANSI_PADDING ON
CREATE TABLE [dbo].[Items](
    [Id] [uniqueidentifier] NOT NULL,
    [DateTimeCreated] [datetimeoffset](7) NOT NULL,
    [AuthorId] [uniqueidentifier] NOT NULL,
    [Source] [varchar](max) NOT NULL,
    [PlaceId] [uniqueidentifier] NULL,
    [FullText] [varchar](max) NOT NULL,
    [Geography] [geography] NULL,
    [DateTimeAdded] [datetime] NULL,
 CONSTRAINT [PK_Items] PRIMARY KEY CLUSTERED ( [Id] ASC ) 
                 WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, 
                 IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, 
                 ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
ALTER TABLE [dbo].[Items]  WITH CHECK ADD  CONSTRAINT [FK_Items_Places] 
FOREIGN KEY([PlaceId]) REFERENCES [dbo].[Places] ([Id])
ALTER TABLE [dbo].[Items] CHECK CONSTRAINT [FK_Items_Places]
GO
ALTER TABLE [dbo].[Items]  WITH CHECK ADD  CONSTRAINT [FK_Items_Users] 
FOREIGN KEY([AuthorId]) REFERENCES [dbo].[Users] ([Id])
ALTER TABLE [dbo].[Items] CHECK CONSTRAINT [FK_Items_Users]

还有我的数据库:

USE [master]
GO
CREATE DATABASE [SocialMedia]
 CONTAINMENT = NONE
 ON  PRIMARY 
 ( NAME = N'SocialMedia', 
   FILENAME = N'C:'Program Files'Microsoft SQL Server'MSSQL11.DENALI'MSSQL'DATA'SocialMedia.mdf' , 
    SIZE = 1110016KB , MAXSIZE = UNLIMITED, FILEGROWTH = 1024KB )
 LOG ON 
( NAME = N'SocialMedia_log', 
  FILENAME = N'C:'Program Files'Microsoft SQL Server'MSSQL11.DENALI'MSSQL'DATA'SocialMedia_log.ldf' , 
  SIZE = 123648KB , MAXSIZE = 2048GB , FILEGROWTH = 10%)
GO
ALTER DATABASE [SocialMedia] SET COMPATIBILITY_LEVEL = 110
GO
IF (1 = FULLTEXTSERVICEPROPERTY('IsFullTextInstalled')) BEGIN
  EXEC [SocialMedia].[dbo].[sp_fulltext_database] @action = 'enable'
END
GO
ALTER DATABASE [SocialMedia] SET ANSI_NULL_DEFAULT OFF 
ALTER DATABASE [SocialMedia] SET ANSI_NULLS ON 
ALTER DATABASE [SocialMedia] SET ANSI_PADDING ON 
ALTER DATABASE [SocialMedia] SET ANSI_WARNINGS ON 
ALTER DATABASE [SocialMedia] SET ARITHABORT ON 
ALTER DATABASE [SocialMedia] SET AUTO_CLOSE OFF 
ALTER DATABASE [SocialMedia] SET AUTO_CREATE_STATISTICS ON 
ALTER DATABASE [SocialMedia] SET AUTO_SHRINK OFF 
ALTER DATABASE [SocialMedia] SET AUTO_UPDATE_STATISTICS ON 
ALTER DATABASE [SocialMedia] SET CURSOR_CLOSE_ON_COMMIT OFF 
ALTER DATABASE [SocialMedia] SET CURSOR_DEFAULT  GLOBAL 
ALTER DATABASE [SocialMedia] SET CONCAT_NULL_YIELDS_NULL ON 
ALTER DATABASE [SocialMedia] SET NUMERIC_ROUNDABORT OFF 
ALTER DATABASE [SocialMedia] SET QUOTED_IDENTIFIER ON 
ALTER DATABASE [SocialMedia] SET RECURSIVE_TRIGGERS OFF 
ALTER DATABASE [SocialMedia] SET  ENABLE_BROKER 
ALTER DATABASE [SocialMedia] SET AUTO_UPDATE_STATISTICS_ASYNC OFF 
ALTER DATABASE [SocialMedia] SET DATE_CORRELATION_OPTIMIZATION OFF 
ALTER DATABASE [SocialMedia] SET TRUSTWORTHY OFF 
ALTER DATABASE [SocialMedia] SET ALLOW_SNAPSHOT_ISOLATION OFF 
ALTER DATABASE [SocialMedia] SET PARAMETERIZATION SIMPLE 
ALTER DATABASE [SocialMedia] SET READ_COMMITTED_SNAPSHOT OFF 
ALTER DATABASE [SocialMedia] SET HONOR_BROKER_PRIORITY OFF 
ALTER DATABASE [SocialMedia] SET RECOVERY FULL 
ALTER DATABASE [SocialMedia] SET  MULTI_USER 
ALTER DATABASE [SocialMedia] SET PAGE_VERIFY CHECKSUM  
ALTER DATABASE [SocialMedia] SET DB_CHAINING OFF 
ALTER DATABASE [SocialMedia] SET FILESTREAM( NON_TRANSACTED_ACCESS = OFF ) 
ALTER DATABASE [SocialMedia] SET TARGET_RECOVERY_TIME = 0 SECONDS 
ALTER DATABASE [SocialMedia] SET  READ_WRITE 

以及我用来运行它的代码:

string connString = ConfigurationManager.ConnectionStrings["ApplicationServices"].ConnectionString;
conn = new SqlConnection(connString);
conn.Open(); // open new connection and create command to notify about all new Chat-Messages in -ROOM_NUMBER- const
using (var sqlCommand = new SqlCommand(GetSearchQueryString(searchItems), conn))
{
    var sqlDependency = new SqlDependency(sqlCommand
    //handle onChange event - this will be fired whenever there is a change in database that affacts our query
    sqlDependency.OnChange += (sender, e) =>
    {
        //change detected - get all messages...
        try
        {
            var sql = GetSearchQueryString(searchItems);
            int count = _entities.ExecuteStoreQuery<Guid>(sql).Count();
            AsyncManager.Parameters["count"] = count;
        }
        finally
        {
            AsyncManager.OutstandingOperations.Decrement();
        }
    };
    sqlCommand.ExecuteNonQuery();
}

我在程序的前面打电话给SqlDependency.Start(ConfigurationManager.ConnectionStrings["ApplicationServices"].ConnectionString);

我错过了什么吗? 我觉得我错过了一些明显的东西...

SqlDependency 简单选择查询始终返回“无效”

我发现SqlDependency 非常脆弱。有时,如果您执行了无效的操作,您总是会立即收到通知。无错误消息。

尝试从查询中删除数据库名称限定。像这样引用该表:dbo.Items

我们按照 http://dimarzionist.wordpress.com/2009/04/01/how-to-make-sql-server-notifications-work/中所述的步骤进行操作

看起来您正在使用三个部分名称,即

[SocialMedia].[dbo].[Items].[Id]

文档明确指出您需要使用两个部分名称,因此

更改为

[SocialMedia].[Items].[Id]

迈克尔的回答是一个很好的来源,但有一件事Microsoft省略了:

SQL 代理将拒绝具有 计算列

如果你尝试,你会得到一个 SqlNotificationEventArgs,其中包含 info=Query,type=Subscribe,并且像我一样,你会花几个小时试图找出语句的问题,而计算列是罪魁祸首。

在 SQl 服务器中执行

使用立即回滚更改数据库 YOURDBNAME 集ENABLE_BROKER