DMSFrame 之SqlCacheDependency（一）

1.SqlCacheDependency都是我们常用的一种Cache写法了。对后面的SQL 2005算是比较成熟的一种缓存模式了，这里介绍一下DMSFrame的SqlCacheDependency是怎么使用的

DMSFrame已内置MSSQL的通知模式(MSSQL2005以上,含2005)和轮循模式(MSSQL2005以下)的缓存写法。

查看数据库是否支持通知模式

SELECT  DATABASEPROPERTYEX('DATABASENAME','IsBrokerEnabled') 1 表示启用，0表示未启用

启用IsBrokerEnabled

ALTER DATABASE [DATABASENAME] SET NEW_BROKER WITH ROLLBACK IMMEDIATE;
ALTER DATABASE [DATABASENAME] SET ENABLE_BROKER;/ALTER DATABASE [DATABASENAME] SET DISABLE_BROKER;

设置权限信息

GRANT SUBSCRIBE QUERY NOTIFICATIONS TO [当前数据库登录用户名，如果是sa可以跳过]

修改登录账号信息,这里比较关键，如果未设置有可能通知是没有权限的。具体也可以看看SQL日志信息

exec sp_changedbowner @loginame = '[当前数据库登录用户名，如果是sa,则使用sa账号]'

首先添加web.config的配置信息

<configSections>
    <section name="DMSLinqCacheProvider" type="DMSFrame.Cache.DMSLinqCacheProvider,DMSFrame"/>
  </configSections>
  <DMSLinqCacheProvider>
    <add key="provider" providerName="MsSql" value="DMSFrame.Cache.DMSLinqSqlWebCacheNotifyProvider,DMSFrame"/>
  </DMSLinqCacheProvider>

最最重要的TableConfig配置数据库加上标记CacheDependency，已便支持CacheDependency

<TableConfiguration>
    <Name>DefaultValue</Name>
    <SqlType>MsSql</SqlType>
    <WithLock>false</WithLock>
    <Author>dbo</Author>
    <CacheDependency>true</CacheDependency>
    <ConnectString>Integrated Security=False;server=127.0.0.1;database=database;User ID=sa;Password=sa;Connect Timeout=30</ConnectString>
  </TableConfiguration>

最后就是查询SQL了,

ToList(bool DependencyFlag) 增加了是否使用缓存的标记参数。

var resultAccess = DMS.Create<Adm_User>()
                .Where(q => q.UserID == )
                .Select(q => q.Columns(q.UserID, q.UpdateTime)).ToList(true);

通知模式的SQL运行跟踪如图：

相关下载：http://files.cnblogs.com/files/kingkoo/DMSFrameRights.zip 此版本为以前的一个版本，最新的版本请加群问群主吧

新上传DMSFrame版本文件:http://files.cnblogs.com/files/kingkoo/DMSFrame_Secure20150606.7z

内置代码引擎如下:

 /// <summary>
    /// 数据库缓存通知模式
    /// 1.SELECT  DATABASEPROPERTYEX('DATABASENAME','IsBrokerEnabled') 1 表示启用，0表示未启用
    /// 2.启用IsBrokerEnabled
    /// ALTER DATABASE [DATABASENAME] SET NEW_BROKER WITH ROLLBACK IMMEDIATE;
    /// ALTER DATABASE [DATABASENAME] SET ENABLE_BROKER;/ALTER DATABASE [DATABASENAME] SET DISABLE_BROKER;
    ///
    /// 3.GRANT SUBSCRIBE QUERY NOTIFICATIONS TO [当前数据库登录用户名，如果是sa可以跳过]
    ///
    /// 4.exec sp_changedbowner @loginame = '[当前数据库登录用户名，如果是sa,则使用sa账号]'
    ///
    /// </summary>
    public class DMSLinqSqlWebCacheNotifyProvider : IDMSLinqCacheProvider
    {

        System.Web.Caching.Cache webCache = System.Web.HttpRuntime.Cache;
        private static object syncObj = new object();
        public DMSLinqSqlWebCacheNotifyProvider()
        {
            lock (syncObj)
            {
                System.Web.HttpContext context = System.Web.HttpContext.Current;
                if (context != null)
                    webCache = context.Cache;
                else
                    webCache = System.Web.HttpRuntime.Cache;
            }
        }

        public string GetDependencyKey(System.Data.IDbCommand command, string[] tableNames)
        {
            string dependencyKey = command.CommandText;
            foreach (System.Data.IDbDataParameter item in command.Parameters)
            {
                dependencyKey += string.Format("-{0}-{1}", item.ParameterName, item.Value);
            }
#if DEBUG
            System.Diagnostics.Debug.WriteLine(string.Format("{0},use dependency key successfully", dependencyKey));
#endif
            return dependencyKey;
        }

        public object GetCache(string dependencyKey)
        {
            object resultValue = webCache[dependencyKey];
#if DEBUG
            System.Diagnostics.Debug.WriteLine(string.Format("this cache is empty?：{0}", resultValue == null ? "true" : "false"));
#endif
            return resultValue;
        }
        public System.Web.Caching.CacheDependency GetCacheDependency(string connectionString, System.Data.IDbCommand command, string[] tableNames, ref string dependencyKey)
        {
            System.Web.Caching.SqlCacheDependency dependency = null;
            try
            {
                dependency = new System.Web.Caching.SqlCacheDependency((System.Data.SqlClient.SqlCommand)command);
            }
            catch (Exception ex)
            {
                DMSFrame.Loggers.LoggerManager.Logger.Log(ex, ReflectionUtils.GetMethodBaseInfo(System.Reflection.MethodBase.GetCurrentMethod()), DMSFrame.Loggers.ErrorLevel.Fatal);
            }
#if DEBUG
            System.Diagnostics.Debug.WriteLine(string.Format("Get the sqlcachedependency successfully.{0}", dependency == null ? "false" : "true"));
#endif
            return dependency;
        }
        public void SetCache(System.Web.Caching.CacheDependency dependency, string dependencyKey, object Value)
        {
            if (dependency != null)
            {
#if DEBUG
                System.Diagnostics.Debug.WriteLine(string.Format("Add cache is successfully,{0}", dependencyKey));
#endif
                webCache.Insert(dependencyKey, Value, dependency);
            }
        }
    }