diff --git a/DD.Persistence.Test/DD.Persistence.Test.csproj b/DD.Persistence.Test/DD.Persistence.Test.csproj
index 9135b1c..8efaa34 100644
--- a/DD.Persistence.Test/DD.Persistence.Test.csproj
+++ b/DD.Persistence.Test/DD.Persistence.Test.csproj
@@ -10,10 +10,15 @@
   <ItemGroup>
     <PackageReference Include="coverlet.collector" Version="6.0.2" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.11.1" />
+    <PackageReference Include="NSubstitute" Version="5.3.0" />
     <PackageReference Include="xunit" Version="2.9.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" />
   </ItemGroup>
 
+  <ItemGroup>
+    <ProjectReference Include="..\DD.Persistence\DD.Persistence.csproj" />
+  </ItemGroup>
+
   <ItemGroup>
     <Using Include="Xunit" />
   </ItemGroup>
diff --git a/DD.Persistence.Test/TimestampedValuesServiceShould.cs b/DD.Persistence.Test/TimestampedValuesServiceShould.cs
index ea19171..5f3e65b 100644
--- a/DD.Persistence.Test/TimestampedValuesServiceShould.cs
+++ b/DD.Persistence.Test/TimestampedValuesServiceShould.cs
@@ -1,19 +1,58 @@
-using DD.Persistence.Repositories;
+using DD.Persistence.Models;
+using DD.Persistence.Repositories;
 using DD.Persistence.Services;
 using NSubstitute;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 
 namespace DD.Persistence.Repository.Test;
 public class TimestampedValuesServiceShould
 {
     private readonly ITimestampedValuesRepository timestampedValuesRepository = Substitute.For<ITimestampedValuesRepository>();
     private readonly IDataSchemeRepository dataSchemeRepository = Substitute.For<IDataSchemeRepository>();
+    private TimestampedValuesService timestampedValuesService;
+
     public TimestampedValuesServiceShould()
     {
-        var timestampedValuesService = new TimestampedValuesService(timestampedValuesRepository, dataSchemeRepository);
+        timestampedValuesService = new TimestampedValuesService(timestampedValuesRepository, dataSchemeRepository);
+    }
+
+    [Fact]
+    public async Task TestServiceEfficiency()
+    {
+        var discriminatorId = Guid.NewGuid();
+        const int count = 10;
+        var dtos = Generate(count, DateTimeOffset.UtcNow);
+        var addRangeResult = await timestampedValuesService
+            .AddRange(discriminatorId, dtos, CancellationToken.None);
+        Assert.Equal(0, addRangeResult);
+
+        var columnNames = new[] { "A", "B", "C", "D" };
+        var geTimestamp = DateTimeOffset.UtcNow
+            .AddHours(-1)
+            .ToUniversalTime();
+        var getResult = await timestampedValuesService
+            .Get(discriminatorId, geTimestamp, columnNames, 0, count, CancellationToken.None);
+        Assert.NotNull(getResult);
+        Assert.Empty(getResult);
+    }
+
+    private static IEnumerable<TimestampedValuesDto> Generate(int countToCreate, DateTimeOffset from)
+    {
+        var result = new List<TimestampedValuesDto>();
+        for (int i = 0; i < countToCreate; i++)
+        {
+            var values = new Dictionary<string, object>()
+            {
+                { "A", i },
+                { "B", i * 1.1 },
+                { "C", $"Any{i}" },
+                { "D", DateTimeOffset.Now },
+            };
+
+            yield return new TimestampedValuesDto()
+            {
+                Timestamp = from.AddSeconds(i),
+                Values = values
+            };
+        }
     }
 }
diff --git a/DD.Persistence.sln b/DD.Persistence.sln
index eeb198c..03f0be9 100644
--- a/DD.Persistence.sln
+++ b/DD.Persistence.sln
@@ -28,6 +28,8 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "SolutionItems", "SolutionIt
 		Directory.Build.props = Directory.Build.props
 	EndProjectSection
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DD.Persistence.Test", "DD.Persistence.Test\DD.Persistence.Test.csproj", "{B8C774E6-6B75-41AC-B3CF-10BD3623B2FA}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -74,6 +76,10 @@ Global
 		{08B03623-A1C9-482F-B60E-09F293E04999}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{08B03623-A1C9-482F-B60E-09F293E04999}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{08B03623-A1C9-482F-B60E-09F293E04999}.Release|Any CPU.Build.0 = Release|Any CPU
+		{B8C774E6-6B75-41AC-B3CF-10BD3623B2FA}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{B8C774E6-6B75-41AC-B3CF-10BD3623B2FA}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{B8C774E6-6B75-41AC-B3CF-10BD3623B2FA}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{B8C774E6-6B75-41AC-B3CF-10BD3623B2FA}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE