diff --git a/BeetleX.Redis.XUnitTest/BeetleX.Redis.XUnitTest.csproj b/BeetleX.Redis.XUnitTest/BeetleX.Redis.XUnitTest.csproj
index 87a64be..f0e1c91 100644
--- a/BeetleX.Redis.XUnitTest/BeetleX.Redis.XUnitTest.csproj
+++ b/BeetleX.Redis.XUnitTest/BeetleX.Redis.XUnitTest.csproj
@@ -6,6 +6,13 @@
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 
+  <ItemGroup>
+    <Compile Remove="DBTester_BACKUP_37104.cs" />
+    <Compile Remove="DBTester_BASE_37104.cs" />
+    <Compile Remove="DBTester_LOCAL_37104.cs" />
+    <Compile Remove="DBTester_REMOTE_37104.cs" />
+  </ItemGroup>
+
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.8.0" />
     <PackageReference Include="Northwind.Data" Version="1.2.3" />
diff --git a/BeetleX.Redis.XUnitTest/DBTester.cs b/BeetleX.Redis.XUnitTest/DBTester.cs
index 5f0dfea..d7b750c 100644
--- a/BeetleX.Redis.XUnitTest/DBTester.cs
+++ b/BeetleX.Redis.XUnitTest/DBTester.cs
@@ -16,14 +16,9 @@ public class DBTester
         public DBTester(ITestOutputHelper output)
         {
             this.Console = output;
-            //DB.Host.AddWriteHost("192.168.2.19", 6378, true);
-<<<<<<< HEAD
-            DB.Host.AddWriteHost("192.168.2.19", 6379);
-=======
             DB.Host.AddWriteHost("127.0.0.1");
-            DB.KeyPrefix = "bbq";
->>>>>>> KeyPrefix
-
+            DB.KeyPrefix = "BeetleX";
+            DB.AutoPing = false;
         }
 
         private RedisDB DB = new RedisDB(0);
@@ -100,7 +95,7 @@ public async void Set()
 
             var emptyValue = await DB.Get<string>("test");
             Write(emptyValue);
-            Assert.Equal<string>(emptyValue, "");
+            Assert.Equal<string>(emptyValue, null);
 
 
             var nullResult = await DB.Set("test", null);
@@ -108,7 +103,7 @@ public async void Set()
 
             var nullValue = await DB.Get<string>("test");
             Write(nullValue);
-            Assert.Equal<string>(nullValue, "");
+            Assert.Equal<string>(nullValue, null);
 
         }
 
diff --git a/BeetleX.Redis.XUnitTest/HashTableTester.cs b/BeetleX.Redis.XUnitTest/HashTableTester.cs
index aa61867..3a3070e 100644
--- a/BeetleX.Redis.XUnitTest/HashTableTester.cs
+++ b/BeetleX.Redis.XUnitTest/HashTableTester.cs
@@ -12,7 +12,7 @@ public HashTableTester(ITestOutputHelper output)
         {
             this.Console = output;
             DB.Host.AddWriteHost("localhost");
-            DB.KeyPrefix = "KV";
+            DB.KeyPrefix = "BeetleX";
         }
 
         private RedisDB DB = new RedisDB(0);
@@ -73,7 +73,7 @@ public async void HGet()
 
             var emptyValue = await table.Get<string>("fieldEmpty");
             Write(emptyValue);
-            Assert.Equal<string>(emptyValue, "");
+            Assert.Equal<string>(emptyValue, null);
 
 
             var nullResult = await table.Set("fieldNull", null);
@@ -81,7 +81,7 @@ public async void HGet()
 
             var nullValue = await table.Get<string>("fieldNull");
             Write(nullValue);
-            Assert.Equal<string>(nullValue, "");
+            Assert.Equal<string>(nullValue, null);
 
 
         }
@@ -134,9 +134,9 @@ public async void HLen()
         public async void HMGet()
         {
             await DB.Flushall();
-            var table = DB.CreateHashTable("myhash");
-            Write(await table.MSet(("field1", "hello"), ("field2", "world")));
-            var values = await table.Get<string, string, string>("field1", "field2", "nofield");
+var table = DB.CreateHashTable("myhash");
+Write(await table.MSet(("field1", "hello"), ("field2", "world")));
+var values = await table.Get<string, string, string>("field1", "field2", "nofield");
             Write(values.Item1);
             Write(values.Item2);
             Write(values.Item3);
diff --git a/BeetleX.Redis.XUnitTest/SequenceTest.cs b/BeetleX.Redis.XUnitTest/SequenceTest.cs
index 9bc6681..06e9084 100644
--- a/BeetleX.Redis.XUnitTest/SequenceTest.cs
+++ b/BeetleX.Redis.XUnitTest/SequenceTest.cs
@@ -14,6 +14,7 @@ public SequenceTest(ITestOutputHelper output)
         {
             this.Console = output;
             DB.Host.AddWriteHost("localhost");
+            DB.KeyPrefix = "BeetleX";
         }
 
         private RedisDB DB = new RedisDB(0);
@@ -50,7 +51,7 @@ public async void ZSCORE()
             var sequeue = DB.CreateSequence("seq2");
             var count = await sequeue.ZAdd((4.14, "bca"));
             var value = await sequeue.ZScore("bca");
-            Assert.Equal<double>(value, 4.14);
+            Assert.Equal<double>(value.Value, 4.14);
 
             var unknownMemberValue = await sequeue.ZScore("unknownseq");
             Assert.Equal<double?>(unknownMemberValue, null);
@@ -64,10 +65,10 @@ public async void ZINCRBY()
             var sequeue = DB.CreateSequence("seq2");
             var count = await sequeue.ZAdd((4.14, member));
             var value = await sequeue.ZScore(member);
-            Assert.Equal<double>(value, 4.14);
+            Assert.Equal<double>(value.Value, 4.14);
             await sequeue.ZIncrby(5, member);
             value = await sequeue.ZScore(member);
-            Assert.Equal<double>(value, 9.14);
+            Assert.Equal<double>(value.Value, 9.14);
         }
         [Fact]
         public async void ZCARD()
@@ -161,7 +162,7 @@ public async void ZRANK()
             var sequeue = DB.CreateSequence("seq2");
             await sequeue.ZAdd((100, "A1"), (200, "A2"), (300, "A3"), (400, "A4"));
             var value = await sequeue.ZRank("A4");
-            Assert.Equal<long>(value, 3);
+            Assert.Equal<long>(value.Value, 3);
 
 
             var unknownMemberValue = await sequeue.ZRank("unknownseq");
diff --git a/BeetleX.Redis.XUnitTest/SetsTester.cs b/BeetleX.Redis.XUnitTest/SetsTester.cs
index c32bc94..93ba538 100644
--- a/BeetleX.Redis.XUnitTest/SetsTester.cs
+++ b/BeetleX.Redis.XUnitTest/SetsTester.cs
@@ -17,7 +17,7 @@ public SetsTester(ITestOutputHelper output)
             DefaultRedis.Instance.Host.AddWriteHost("localhost");
             DefaultRedis.Instance.DataFormater = new JsonFormater();
             DB = DefaultRedis.Instance.Cloneable();
-            DB.KeyPrefix = "HENRY";
+            DB.KeyPrefix = "BeetleX";
         }
 
         private RedisDB DB;
diff --git a/src/BeetleX.Redis.csproj b/src/BeetleX.Redis.csproj
index 70b851c..7252f21 100644
--- a/src/BeetleX.Redis.csproj
+++ b/src/BeetleX.Redis.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>    
     <TargetFrameworks>netcoreapp2.1;netcoreapp3.1</TargetFrameworks>
-    <Version>1.2.4</Version>
+    <Version>1.3.1</Version>
     <Company>beetlex.io</Company>
     <Authors>henryfan</Authors>
     <Copyright>Copyright © beetlex.io 2019-2021</Copyright>
@@ -17,11 +17,11 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="BeetleX" Version="1.6.5.41" />
+    <PackageReference Include="BeetleX" Version="1.6.5.62" />
     <PackageReference Include="BeetleX.Tracks" Version="0.7.5" />
     <PackageReference Include="MessagePack" Version="2.1.115" />
     <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
-    <PackageReference Include="protobuf-net" Version="2.4.6" />
+    <PackageReference Include="protobuf-net" Version="3.0.101" />
     <PackageReference Include="System.Text.Json" Version="5.0.2" />
   </ItemGroup>
 
diff --git a/src/Command.cs b/src/Command.cs
index dee2bac..9538111 100644
--- a/src/Command.cs
+++ b/src/Command.cs
@@ -29,6 +29,8 @@ static Command()
 
         public static byte[] GetMsgHeaderLengthData(int length)
         {
+            if (length <= 0)
+                return null;
             if (length > MAX_LENGTH_TABLE)
                 return null;
             return mMsgHeaderLenData[length - 1];
@@ -38,6 +40,8 @@ public static byte[] GetMsgHeaderLengthData(int length)
 
         public static byte[] GetBodyHeaderLenData(int length)
         {
+            if (length <= 0)
+                return null;
             if (length > MAX_LENGTH_TABLE)
                 return null;
             return mBodyHeaderLenData[length - 1];
diff --git a/src/Commands/HSET.cs b/src/Commands/HSET.cs
index 9050add..62df066 100644
--- a/src/Commands/HSET.cs
+++ b/src/Commands/HSET.cs
@@ -29,6 +29,8 @@ public override void OnExecute()
             base.OnExecute();
             OnWriteKey(Key);
             AddText(Field);
+            if (Value == null)
+                Value = string.Empty;
             AddData(Value);
         }
 
diff --git a/src/Commands/SET.cs b/src/Commands/SET.cs
index fb0aa80..b5dbff1 100644
--- a/src/Commands/SET.cs
+++ b/src/Commands/SET.cs
@@ -31,6 +31,8 @@ public override void OnExecute()
         {
             base.OnExecute();
             OnWriteKey(Key);
+            if (Data == null)
+                Data = string.Empty;
             AddData(Data);
             if (TimeOut > 0)
             {
diff --git a/src/Commands/ZUNIONSTORE.cs b/src/Commands/ZUNIONSTORE.cs
index 69e5f7f..8189f93 100644
--- a/src/Commands/ZUNIONSTORE.cs
+++ b/src/Commands/ZUNIONSTORE.cs
@@ -37,7 +37,7 @@ public override void OnExecute()
             AddText(Items.Length);
             foreach (var item in Items)
             {
-                AddText(item.key);
+                OnWriteKey(item.key);
             }
             AddText("WEIGHTS");
             foreach (var item in Items)
diff --git a/src/RedisDB.cs b/src/RedisDB.cs
index 276cf68..0ddf21e 100644
--- a/src/RedisDB.cs
+++ b/src/RedisDB.cs
@@ -90,6 +90,7 @@ public RedisStream<T> GetStream<T>(string name)
         public RedisDB Cloneable(IDataFormater dataFormater = null)
         {
             var result = new RedisDB(this.DB, dataFormater, this);
+            result.KeyPrefix = this.KeyPrefix;
             return result;
         }
 
@@ -163,7 +164,7 @@ public async Task<Result> Execute(Command cmd, params Type[] types)
                 return new Result() { ResultType = ResultType.NetError, Messge = "exceeding maximum number of connections" };
             try
             {
-                var result = host.Connect(this,client);
+                var result = host.Connect(this, client);
                 if (result.IsError)
                 {
                     return result;
@@ -661,7 +662,7 @@ public async Task PFMerge(string key, params string[] items)
                 throw new RedisException(result.Messge);
         }
 
-     
+
 
 
         public async ValueTask<InfoResult> Info(InfoSection? section = null)
diff --git a/src/Sequence.cs b/src/Sequence.cs
index 47472dc..0c53fff 100644
--- a/src/Sequence.cs
+++ b/src/Sequence.cs
@@ -28,12 +28,14 @@ public async ValueTask<long> ZAdd(params (double, string)[] items)
             return (long)result.Value;
         }
 
-        public async ValueTask<double> ZScore(string member)
+        public async ValueTask<double?> ZScore(string member)
         {
             ZSCORE cmd = new ZSCORE(Key, member);
             var result = await DB.Execute(cmd, typeof(string));
             if (result.IsError)
                 throw new RedisException(result.Messge);
+            if (result.Value == null)
+                return null;
             return System.Convert.ToDouble(result.Value);
         }
 
@@ -114,12 +116,14 @@ public async ValueTask<long> ZCount(double min, double max)
             return GetItems(result, withscores);
         }
 
-        public async ValueTask<long> ZRank(string member)
+        public async ValueTask<long?> ZRank(string member)
         {
             ZRANK cmd = new ZRANK(Key, member);
             var result = await DB.Execute(cmd, typeof(string));
             if (result.IsError)
                 throw new RedisException(result.Messge);
+            if (result.Value == null)
+                return null;
             return System.Convert.ToInt64(result.Value);
         }
 
@@ -211,7 +215,7 @@ public ValueTask<long> ZUnionsStore(params string[] keys)
             return ZUnionsStore(items);
         }
 
-        public  ValueTask<long> ZUnionsStore(params (string key, double weight)[] items)
+        public ValueTask<long> ZUnionsStore(params (string key, double weight)[] items)
         {
             return ZUnionsStore(items, ZUNIONSTORE.AggregateType.SUM);
         }