diff --git a/DD.Persistence.Models/DataSchemeDto.cs b/DD.Persistence.Models/DataSchemeDto.cs
index d20ffaa..2b28176 100644
--- a/DD.Persistence.Models/DataSchemeDto.cs
+++ b/DD.Persistence.Models/DataSchemeDto.cs
@@ -18,7 +18,7 @@ public class DataSchemeDto : IEnumerable<SchemePropertyDto>, IEquatable<IEnumera
     private IEnumerable<SchemePropertyDto> Properties { get; }  = [];
 
     /// <inheritdoc/>
-    public DataSchemeDto(Guid discriminatorId, SchemePropertyDto[] Properties)
+    public DataSchemeDto(Guid discriminatorId, IEnumerable<SchemePropertyDto> Properties)
     {
         DiscriminatorId = discriminatorId;
         this.Properties = Properties;
@@ -34,8 +34,8 @@ public class DataSchemeDto : IEnumerable<SchemePropertyDto>, IEquatable<IEnumera
     /// <inheritdoc/>
     public bool Equals(IEnumerable<SchemePropertyDto>? otherProperties)
     {
-        //if (otherProperties is null)
-        //    return false;
+        if (otherProperties is null)
+            return false;
 
         return Properties.SequenceEqual(otherProperties);
     }
diff --git a/DD.Persistence/Services/TimestampedValuesService.cs b/DD.Persistence/Services/TimestampedValuesService.cs
index 5e6f9ed..cef700f 100644
--- a/DD.Persistence/Services/TimestampedValuesService.cs
+++ b/DD.Persistence/Services/TimestampedValuesService.cs
@@ -117,13 +117,13 @@ public class TimestampedValuesService : ITimestampedValuesService
             if (dataScheme is null)
                 continue;
 
-            foreach (var tuple in keyValuePair.Value)
+            foreach (var (Timestamp, Values) in keyValuePair.Value)
             {
                 var dto = new TimestampedValuesDto()
                 {
-                    Timestamp = tuple.Timestamp.ToUniversalTime(),
+                    Timestamp = Timestamp.ToUniversalTime(),
                     Values = dataScheme
-                        .ToDictionary(k => k.PropertyName, v => tuple.Values[v.Index])
+                        .ToDictionary(k => k.PropertyName, v => Values[v.Index])
                 };
 
                 result = result.Append(dto);
@@ -144,11 +144,12 @@ public class TimestampedValuesService : ITimestampedValuesService
     private async Task CreateDataSchemeIfNotExist(Guid discriminatorId, TimestampedValuesDto dto, CancellationToken token)
     {
         var valuesList = dto.Values.ToList();
-        var properties = valuesList.ToList().Select(e => new SchemePropertyDto() {
-            Index = valuesList.IndexOf(e),
+        var properties = valuesList.Select((e, index) => new SchemePropertyDto()
+        {
+            Index = index,
             PropertyName = e.Key,
-            PropertyKind = ((JsonElement) e.Value).ValueKind
-        }).ToArray();
+            PropertyKind = ((JsonElement)e.Value).ValueKind
+        });
 
         var dataScheme = await dataSchemeRepository.Get(discriminatorId, token);
         if (dataScheme is null)
@@ -172,7 +173,7 @@ public class TimestampedValuesService : ITimestampedValuesService
     /// <param name="dtos"></param>
     /// <param name="fieldNames">Поля, которые необходимо оставить</param>
     /// <returns></returns>
-    private IEnumerable<TimestampedValuesDto> ReduceSetColumnsByNames(IEnumerable<TimestampedValuesDto> dtos, IEnumerable<string> fieldNames)
+    private static IEnumerable<TimestampedValuesDto> ReduceSetColumnsByNames(IEnumerable<TimestampedValuesDto> dtos, IEnumerable<string> fieldNames)
     {
         var result = dtos.Select(dto =>
         {