diff --git a/GBase.Api/IGBaseObject.cs b/GBase.Api/IGBaseObject.cs
index 67d6483..7319dd8 100644
--- a/GBase.Api/IGBaseObject.cs
+++ b/GBase.Api/IGBaseObject.cs
@@ -11,11 +11,16 @@ namespace GBase.Api
     /// </summary>
     public interface IGBaseObject
     {
+        /// <summary>
+        /// The FileName of the GBase file for an entry of this object
+        /// </summary>
+        string FileName { get; }
+        
         /// <summary>
         /// Initialize this <see cref="IGBaseObject"/> from a given <see cref="string"/>
         /// </summary>
         /// <param name="string">The given <see cref="string"/></param>
-        void InitializeFromString(string @string);
+        void InitializeFromString(string @string); //TODO: Try to remove this method, work with keys
 
         void Initialize(List<object> parameters);
     }
diff --git a/GBase/FileHandling/FileHandler.cs b/GBase/FileHandling/FileHandler.cs
index 58162dc..17cba08 100644
--- a/GBase/FileHandling/FileHandler.cs
+++ b/GBase/FileHandling/FileHandler.cs
@@ -7,6 +7,7 @@ using System.IO;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
+using GBase.Api;
 using GBase.FileHandling.Exceptions;
 using GBase.Interfaces;
 using GBase.Interfaces.FileHandling;
@@ -60,7 +61,7 @@ namespace GBase.FileHandling
             return _files;
         }
 
-        public IGBaseFile CreateEntryFile<T>(T entry, IGBaseTable table)
+        public IGBaseFile CreateEntryFile<T>(T entry, IGBaseTable table) where T : IGBaseObject //TODO: Use IGBaseObject as T, add method like GetFilename()
         {
             string directoryPath = Path.Combine(_path, table.FolderName);
             
@@ -68,7 +69,7 @@ namespace GBase.FileHandling
             Directory.CreateDirectory(directoryPath);
             
             //create new entry file
-            string filePath = $"{Path.Combine(directoryPath, entry.ToString())}.{GBASE_TABLE_FILE_EXTENSION}";
+            string filePath = $"{Path.Combine(directoryPath, entry.FileName)}.{GBASE_TABLE_FILE_EXTENSION}";
 
             //check if file is already opened
             IGBaseFile file = _files.FirstOrDefault(f => f.FilePath.Equals(filePath));
diff --git a/GBase/GBaseObject.cs b/GBase/GBaseObject.cs
index 24a355d..57c5401 100644
--- a/GBase/GBaseObject.cs
+++ b/GBase/GBaseObject.cs
@@ -29,6 +29,8 @@ namespace GBase
                 throw new MissingTableException<T>();
         }
 
+        public abstract string FileName { get; }
+        
         protected async Task SetValue<TProperty>(T @this, string propertyName, TProperty value, CancellationToken cancellationToken) =>
             await _gBaseTable.SetValue(@this, propertyName, value, cancellationToken);
 
@@ -37,7 +39,7 @@ namespace GBase
         
         protected async Task<IEnumerable<TProperty>> GetValues<TProperty>(T @this, string propertyName, CancellationToken cancellationToken) =>
             await _gBaseTable.GetValues<TProperty>(@this, propertyName, cancellationToken);
-        
+
         /// <summary>
         /// Initialize this <see cref="GBaseObject{T}"/> from a given <see cref="string"/>
         /// </summary>
diff --git a/GBase/Interfaces/FileHandling/IFileHandler.cs b/GBase/Interfaces/FileHandling/IFileHandler.cs
index e0f9497..1c8fb4e 100644
--- a/GBase/Interfaces/FileHandling/IFileHandler.cs
+++ b/GBase/Interfaces/FileHandling/IFileHandler.cs
@@ -6,6 +6,7 @@ using System;
 using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
+using GBase.Api;
 
 namespace GBase.Interfaces.FileHandling
 {
@@ -23,7 +24,7 @@ namespace GBase.Interfaces.FileHandling
         /// <returns>True if successful, false if not</returns>
         List<IGBaseFile> Init(string path, string folderName, CancellationToken cancellationToken);
 
-        IGBaseFile CreateEntryFile<T>(T entry, IGBaseTable table);
+        IGBaseFile CreateEntryFile<T>(T entry, IGBaseTable table) where T : IGBaseObject;
 
         Task<bool> DeleteEntryFile<T>(T entry);
 
diff --git a/Test.GBase/GBaseIntegrationTest/Group.cs b/Test.GBase/GBaseIntegrationTest/Group.cs
index 0976ea5..97c7908 100644
--- a/Test.GBase/GBaseIntegrationTest/Group.cs
+++ b/Test.GBase/GBaseIntegrationTest/Group.cs
@@ -24,6 +24,7 @@ namespace Test.GBase.GBaseIntegrationTest
         [GBaseColumn]
         public int Key { get; private set; }
         public List<IItem> Items { get; }
+        public string FileName => $"Group{Key}";
 
         public override string ToString() => $"{Key}";
         public void InitializeFromString(string @string) => Key = int.Parse(@string);
diff --git a/Test.GBase/GBaseIntegrationTest/Item.cs b/Test.GBase/GBaseIntegrationTest/Item.cs
index 44e38f5..19ccdf3 100644
--- a/Test.GBase/GBaseIntegrationTest/Item.cs
+++ b/Test.GBase/GBaseIntegrationTest/Item.cs
@@ -26,8 +26,9 @@ namespace Test.GBase.GBaseIntegrationTest
         
         [GBaseColumn]
         public int Key { get; private set; }
+        public string FileName => Name;
 
-        public override string ToString() => $"{Name}";
+        public override string ToString() => $"{Key}/{Name}";
 
         public void InitializeFromString(string @string)
         {
diff --git a/Test.GBase/TestClasses/Foo.cs b/Test.GBase/TestClasses/Foo.cs
index 9213c15..1ebc020 100644
--- a/Test.GBase/TestClasses/Foo.cs
+++ b/Test.GBase/TestClasses/Foo.cs
@@ -35,6 +35,8 @@ namespace Test.GBase.TestClasses
             }
         }
 
+        public string FileName => Name;
+
         public void InitializeFromString(string @string)
         {
             throw new NotImplementedException();
diff --git a/Test.GBase/TestClasses/UserType.cs b/Test.GBase/TestClasses/UserType.cs
index 53cf071..f5173c2 100644
--- a/Test.GBase/TestClasses/UserType.cs
+++ b/Test.GBase/TestClasses/UserType.cs
@@ -22,6 +22,8 @@ namespace Test.GBase.TestClasses
 
         private int Number { get; set; }
 
+        public string FileName { get; }
+
         public void InitializeFromString(string @string)
         {
             string numberString = @string.Split('_').Last();