diff --git a/.github/workflows/validate.yml b/.github/workflows/validate.yml
index 068893fb..493eb2ac 100644
--- a/.github/workflows/validate.yml
+++ b/.github/workflows/validate.yml
@@ -17,7 +17,7 @@ jobs:
       - name: Build project
         run: dotnet build
       - name: Run unit tests
-        run: dotnet test --logger "console;verbosity=detailed"
+        run: dotnet test --logger "console;verbosity=detailed" -graphBuild:True
       - name: Code Coverage Report
         uses: irongut/CodeCoverageSummary@v1.3.0
         with:
diff --git a/Core/Cosmos.DataTransfer.Core.UnitTests/SettingsCommandTests.cs b/Core/Cosmos.DataTransfer.Core.UnitTests/SettingsCommandTests.cs
index b3b48927..8fe62aef 100644
--- a/Core/Cosmos.DataTransfer.Core.UnitTests/SettingsCommandTests.cs
+++ b/Core/Cosmos.DataTransfer.Core.UnitTests/SettingsCommandTests.cs
@@ -17,6 +17,8 @@ namespace Cosmos.DataTransfer.Core.UnitTests
     [TestClass]
     public class SettingsCommandTests
     {
+        // TODO: What is the purpose of this test?
+        // It seems to be a very elaborate method to assert parsing null.
         [TestMethod]
         public void Invoke_ForTestExtension_ProducesValidSettingsJson()
         {
@@ -65,8 +67,10 @@ public void Invoke_ForTestExtension_ProducesValidSettingsJson()
                 WriteIndented = true
             };
             var fullJson = stringBuilder.ToString().Trim();
+            Assert.AreEqual("null", fullJson);
             var parsed = JsonSerializer.Deserialize<List<ExtensionSettingProperty>>(fullJson, options);
-            var parsedJson = JsonSerializer.Serialize<List<ExtensionSettingProperty>>(parsed, options);
+            Assert.IsNull(parsed);
+            var parsedJson = JsonSerializer.Serialize<List<ExtensionSettingProperty>>(parsed!, options);
 
             Assert.AreEqual(fullJson, parsedJson);
         }
diff --git a/Extensions/PostgreSQL/PostgreDataCol.cs b/Extensions/PostgreSQL/PostgreDataCol.cs
index 9cf23ff3..080fe7b7 100644
--- a/Extensions/PostgreSQL/PostgreDataCol.cs
+++ b/Extensions/PostgreSQL/PostgreDataCol.cs
@@ -35,8 +35,11 @@ public PostgreDataCol(string colname, string postgredatatye)
             ColumnType = Convert(PostgreType);
         }
 
-        public PostgreDataCol()
+        public PostgreDataCol(string colname, Type coltype, NpgsqlTypes.NpgsqlDbType postgredatatye)
         {
+            ColumnName = colname;
+            PostgreType = postgredatatye;
+            ColumnType = coltype;
         }
 
         public Dictionary<long, object> SparseColumnData { get; } = new Dictionary<long, object>();
diff --git a/Extensions/PostgreSQL/PostgresqlDataSinkExtension.cs b/Extensions/PostgreSQL/PostgresqlDataSinkExtension.cs
index 8f16dce2..397fcd80 100644
--- a/Extensions/PostgreSQL/PostgresqlDataSinkExtension.cs
+++ b/Extensions/PostgreSQL/PostgresqlDataSinkExtension.cs
@@ -86,7 +86,7 @@ private async Task<List<PostgreDataCol>> FindPostgreDataTypes(IAsyncEnumerable<I
                     {
                         if (current.PostgreType == NpgsqlTypes.NpgsqlDbType.Unknown && coltype?.Name != "Missing")
                         {
-                            var newcol = new PostgreDataCol(col, coltype);
+                            var newcol = new PostgreDataCol(col, coltype!);
                             postgreDataCols[row] = newcol;
                         }
                     }
@@ -106,12 +106,7 @@ private List<PostgreDataCol> MapDataTypes(List<PostgreDataCol> dest, List<Postgr
                 {
                     if (item.ColumnName.ToLower() == col.ColumnName.ToLower())
                     {
-                        temp.Add(new PostgreDataCol()
-                        {
-                            ColumnName = col.ColumnName,
-                            ColumnType = item.ColumnType,
-                            PostgreType = item.PostgreType
-                        });
+                        temp.Add(new PostgreDataCol(col.ColumnName, item.ColumnType, item.PostgreType));
                         found = true;
                         break;
                     }
@@ -169,7 +164,7 @@ private static List<PostgreDataCol> LoadTableSchema(NpgsqlConnection con, string
             {
                 if (row != null)
                 {
-                    var newcol = new PostgreDataCol(row["column_name"]?.ToString(), row["udt_name"]?.ToString());
+                    var newcol = new PostgreDataCol(row["column_name"]?.ToString()!, row["udt_name"]?.ToString()!);
                     temp.Add(newcol);
                 }
             }
diff --git a/Extensions/PostgreSQL/Settings/PostgreSinkSettings.cs b/Extensions/PostgreSQL/Settings/PostgreSinkSettings.cs
index 3ab0bde4..4f9aef42 100644
--- a/Extensions/PostgreSQL/Settings/PostgreSinkSettings.cs
+++ b/Extensions/PostgreSQL/Settings/PostgreSinkSettings.cs
@@ -6,7 +6,9 @@ namespace Cosmos.DataTransfer.PostgresqlExtension.Settings
     public class PostgreSinkSettings : PostgreBaseSettings
     {
         [Required]
+#pragma warning disable CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
         public string TableName { get; set; }
+#pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring as nullable.
         public bool? AppendDataToTable { get; set; }
         public bool? DropAndCreateTable { get; set; }
 
diff --git a/Extensions/PostgreSQL/Settings/PostgreSourceSettings.cs b/Extensions/PostgreSQL/Settings/PostgreSourceSettings.cs
index 96549f3d..b73028bb 100644
--- a/Extensions/PostgreSQL/Settings/PostgreSourceSettings.cs
+++ b/Extensions/PostgreSQL/Settings/PostgreSourceSettings.cs
@@ -7,7 +7,7 @@ public class PostgreSourceSettings:PostgreBaseSettings
     {
         [Required]
         [SensitiveValue]
-        public string? ConnectionString { get; set; }
+        public new string? ConnectionString { get; set; }
 
         [Required]
         public string? QueryText { get; set; }
diff --git a/Interfaces/Cosmos.DataTransfer.Interfaces/ValidationExtensions.cs b/Interfaces/Cosmos.DataTransfer.Interfaces/ValidationExtensions.cs
index 78230572..ad05f37c 100644
--- a/Interfaces/Cosmos.DataTransfer.Interfaces/ValidationExtensions.cs
+++ b/Interfaces/Cosmos.DataTransfer.Interfaces/ValidationExtensions.cs
@@ -4,7 +4,7 @@ namespace Cosmos.DataTransfer.Interfaces;
 
 public static class ValidationExtensions
 {
-    public static IEnumerable<string?> GetValidationErrors<T>(this T? settings)
+    public static IEnumerable<string> GetValidationErrors<T>(this T? settings)
         where T : class, IDataExtensionSettings, new()
     {
         if (settings == null)
@@ -18,7 +18,10 @@ public static class ValidationExtensions
         Validator.TryValidateObject(settings, context, results, true);
         foreach (var validationResult in results)
         {
-            yield return validationResult.ErrorMessage;
+            if (validationResult.ErrorMessage is not null)
+            {
+                yield return validationResult.ErrorMessage;
+            }
         }
     }