使用StackExchange.Redis组件C#模糊删除模糊查找

Leo_wlCnBlogs / 2023-05-05 / 原文

C# StackExchange.Redis 模糊删除模糊查找

 /// <summary>
        /// 模糊查找
        /// </summary>
        /// <param name="key"></param>
        public List<XJDataDll.Tag.Point> SelectTags(string pattern)
        {
            List<XJDataDll.Tag.Point> result = new List<XJDataDll.Tag.Point>();
            try
            {


                var redisResult = _Redisconnection.GetDatabase().ScriptEvaluate(LuaScript.Prepare(
                                //Redis的keys模糊查询：
                                " local res = redis.call('KEYS', @keypattern) " +
                                " return res "), new { @keypattern = pattern });

                if (!redisResult.IsNull)
                {
                    RedisKey[] preSult = (RedisKey[])redisResult;
                    var Tags = _Redisconnection.GetDatabase().StringGet(preSult);

                    if (Tags != null)
                    {
                        result = Tags.Select(o => XJDataDll.Json.DataJsonSerializer.JsonToObject<XJDataDll.Tag.Point>(o.ToString())).ToList();
                    }
                }



            }
            catch (Exception ex)
            {

                Console.WriteLine(ex.Message);
            }
            finally
            {
                if (result == null)
                {
                    result = new List<XJDataDll.Tag.Point>();
                }
            }

            return result;
        }

    /// <summary>
        /// 模糊删除
        /// </summary>
        /// <param name="key"></param>
        public void LikeRemove(string pattern)
        {
            try
            {


                var redisResult = _Redisconnection.GetDatabase().ScriptEvaluate(LuaScript.Prepare(
                                //Redis的keys模糊查询：
                                " local res = redis.call('KEYS', @keypattern) " +
                                " return res "), new { @keypattern = pattern });

                if (!redisResult.IsNull)
                {
                    RedisKey[] preSult = (RedisKey[])redisResult;
                    _Redisconnection.GetDatabase().KeyDelete(preSult);
                }
            }
            catch (Exception ex)
            {

                Console.WriteLine(ex.Message);
            }
        }

StackExchange.Redis 模糊查询和删除

初始化连接对象

_connectionString = ConfigurationManager.ConnectionStrings["RedisConnectionString"].ConnectionString;
_connMultiplexer = ConnectionMultiplexer.Connect(_connectionString);
_db = _connMultiplexer.GetDatabase(db);

通过 keys或scan查找出匹配的key，StackExchange.Redis 中调用 keys/scan/size/flush/save/集群等命令须使用 IServer 对象

_server = _connMultiplexer.GetServer(_connMultiplexer.GetEndPoints()[0]); //默认一个服务器
var pattern = "BUIK_201710*";
var keys = _server.Keys(database: _db.Database, pattern: pattern); //StackExchange.Redis 会根据redis版本决定用keys还是scan(>2.8) 
return _db.KeyDelete(keys.ToArray()); //删除一组key

如果数据量很大（比如几十万个key），以上操作会很慢，甚至超时，原因未知，因为通过命令执行keys是很快的

为了提高效率，可以通过Lua脚本进行模糊查询的批量操作

var pattern = "BUIK_201710*";
var redisResult = await _db.ScriptEvaluateAsync(LuaScript.Prepare(
                //Redis的keys模糊查询：
                " local res = redis.call('KEYS', @keypattern) " +
                " return res "), new { @keypattern = pattern });

if (!redisResult.IsNull) {
　　_db.KeyDelete((string[])redisResult);  //删除一组key
}