diff --git a/Assets/Scripts/EntityType.cs b/Assets/Scripts/EntityType.cs
index a9fcee7..e736fbc 100644
--- a/Assets/Scripts/EntityType.cs
+++ b/Assets/Scripts/EntityType.cs
@@ -2,8 +2,7 @@ namespace ECSTest
 {
     public enum EntityType
     {
-        Unit,
-        Monster,
+        Cannon,
         Bullet,
     }
 
diff --git a/Assets/Scripts/Server/WorldManager.cs b/Assets/Scripts/Server/WorldManager.cs
index e5a40a2..d2beba7 100644
--- a/Assets/Scripts/Server/WorldManager.cs
+++ b/Assets/Scripts/Server/WorldManager.cs
@@ -4,7 +4,6 @@ namespace ECSTest.Server
 {
     public struct WorldManager
     {
-        public EntityCollection<EntityType> entities;
-        public EntityDataBlockChain chain;
+        public EntityDatabase<EntityType, EntityDataBlockChain> bulletDatabase;
     }
 }
\ No newline at end of file
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.cs.meta b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.cs.meta
deleted file mode 100644
index 26e07fa..0000000
--- a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.cs.meta
+++ /dev/null
@@ -1,3 +0,0 @@
-fileFormatVersion: 2
-guid: 24392c1216204b6ea64acd57bb43441b
-timeCreated: 1668251924
\ No newline at end of file
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.gen.cs.meta b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.gen.cs.meta
deleted file mode 100644
index 0f7795a..0000000
--- a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.gen.cs.meta
+++ /dev/null
@@ -1,3 +0,0 @@
-fileFormatVersion: 2
-guid: c9227b743e78463b8df770cefc98fb18
-timeCreated: 1668274486
\ No newline at end of file
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataSet.cs b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataSet.cs
deleted file mode 100644
index 292f144..0000000
--- a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataSet.cs
+++ /dev/null
@@ -1,14 +0,0 @@
-using System;
-using Unity.Collections;
-using Unity.Mathematics;
-
-namespace GameCore.TinyECS
-{
-    public struct EntityDataSet : IDisposable
-    {
-        public void Dispose()
-        {
-            //TODO
-        }
-    }
-}
\ No newline at end of file
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.cs b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.cs
similarity index 98%
rename from LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.cs
rename to LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.cs
index c13670e..7fccb7f 100644
--- a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.cs
+++ b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.cs
@@ -13,7 +13,7 @@ namespace GameCore.TinyECS
         public int elementAlign;
     }
 
-    public unsafe struct EntityDataBlockChain : IDisposable
+    public unsafe struct EntityDataBlockChain : IEntityDataStruct
     {
         public readonly EntityDataBlockMeta blockMeta;
         private FixedList512Bytes<IntPtr> blockPtrList;
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.cs.meta b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.cs.meta
new file mode 100644
index 0000000..13c2320
--- /dev/null
+++ b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 7b0b5bb1c56f2114ba60d9154d447872
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.gen.cs b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.gen.cs
similarity index 100%
rename from LocalPackages/com.nimin.tinyecs/Runtime/EntityDataBlock.gen.cs
rename to LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.gen.cs
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.gen.cs.meta b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.gen.cs.meta
new file mode 100644
index 0000000..c43ca48
--- /dev/null
+++ b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.Block.gen.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 747b2bec360ee8141b0b46886b09f92d
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.cs b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.cs
new file mode 100644
index 0000000..91311dc
--- /dev/null
+++ b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.cs
@@ -0,0 +1,10 @@
+using System;
+
+namespace GameCore.TinyECS
+{
+    public interface IEntityDataStruct : IDisposable
+    {
+        void Add();
+        void Remove(int index);
+    }
+}
\ No newline at end of file
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.cs.meta b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.cs.meta
new file mode 100644
index 0000000..8a3e971
--- /dev/null
+++ b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataStruct.cs.meta
@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: 933c4528e6cf415dbfb79a148896839d
+timeCreated: 1765943532
\ No newline at end of file
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDatabase.cs b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDatabase.cs
new file mode 100644
index 0000000..8f0e839
--- /dev/null
+++ b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDatabase.cs
@@ -0,0 +1,35 @@
+using System;
+using Unity.Collections;
+using Unity.Mathematics;
+
+namespace GameCore.TinyECS
+{
+    public struct EntityDatabase<TEnum, TData> : IDisposable where TEnum : unmanaged where TData : unmanaged, IEntityDataStruct
+    {
+        public TData dataStruct;
+        public EntityGenerator<TEnum> generator;
+        public EntityCollection<TEnum> collection;
+
+        public Entity<TEnum> AddEntity()
+        {
+            var entity = generator.Create();
+            collection.Add(entity);
+            dataStruct.Add();
+            return entity;
+        }
+
+        public void RemoveEntity(Entity<TEnum> entity)
+        {
+            generator.Delete(entity);
+            if (collection.Remove(entity, out var index, out var _))
+                dataStruct.Remove(index);
+        }
+
+        public void Dispose()
+        {
+            generator.Dispose();
+            collection.Dispose();
+            dataStruct.Dispose();
+        }
+    }
+}
\ No newline at end of file
diff --git a/LocalPackages/com.nimin.tinyecs/Runtime/EntityDataSet.cs.meta b/LocalPackages/com.nimin.tinyecs/Runtime/EntityDatabase.cs.meta
similarity index 100%
rename from LocalPackages/com.nimin.tinyecs/Runtime/EntityDataSet.cs.meta
rename to LocalPackages/com.nimin.tinyecs/Runtime/EntityDatabase.cs.meta