diff --git a/DatabaseSchemaReader/SqlGen/MigrationGenerator.cs b/DatabaseSchemaReader/SqlGen/MigrationGenerator.cs
index c92ceb0d..0db17fdb 100644
--- a/DatabaseSchemaReader/SqlGen/MigrationGenerator.cs
+++ b/DatabaseSchemaReader/SqlGen/MigrationGenerator.cs
@@ -65,6 +65,11 @@ public string AddTable(DatabaseTable databaseTable)
             return tableGenerator.Write().Trim();
         }
 
+        private string SanitizeExpression(string expression)
+        {
+            return expression.Replace("\"", "").Replace("[", "").Replace("]", "");
+        }
+
         public virtual string AddColumn(DatabaseTable databaseTable, DatabaseColumn databaseColumn)
         {
             var tableGenerator = CreateTableGenerator(databaseTable);
@@ -84,10 +89,21 @@ public virtual string AddColumn(DatabaseTable databaseTable, DatabaseColumn data
                 {
                     addColumn += " DEFAULT CURRENT_TIMESTAMP";
                 }
+                //is there a named check constraint?
+                //check constraints don't have columns, so simply try to find the column name in the expression
+                //column name may be quoted or [bracketed] but so we do a dumb sanitize
+                var notNullExpression = $"{databaseColumn.Name} IS NOT NULL";
+                var nnc = databaseTable.CheckConstraints.FirstOrDefault(cc =>
+                    SanitizeExpression(cc.Expression).Equals(notNullExpression, StringComparison.OrdinalIgnoreCase));
+                if (nnc != null)
+                {
+                    addColumn += " CONSTRAINT " + Escape(nnc.Name);
+                }
                 //make sure the NOT NULL is AFTER the default
                 if (!addColumn.EndsWith(" NOT NULL"))
                 {
-                    addColumn = addColumn.Replace(" NOT NULL ", " ") + " NOT NULL";
+
+                    addColumn = $"{addColumn.Replace(" NOT NULL ", " ")} NOT NULL";
                 }
             }
             return string.Format(CultureInfo.InvariantCulture,
diff --git a/DatabaseSchemaReaderTest/SqlGen/Migrations/UnitTests/MigrationAddColumn.cs b/DatabaseSchemaReaderTest/SqlGen/Migrations/UnitTests/MigrationAddColumn.cs
index ea7a56be..26f18e28 100644
--- a/DatabaseSchemaReaderTest/SqlGen/Migrations/UnitTests/MigrationAddColumn.cs
+++ b/DatabaseSchemaReaderTest/SqlGen/Migrations/UnitTests/MigrationAddColumn.cs
@@ -117,6 +117,34 @@ public void TestOracleNoSchema()
             Assert.IsTrue(sql.StartsWith("ALTER TABLE \"Orders\" ADD \"COUNTRY\" NVARCHAR2 (20)", StringComparison.OrdinalIgnoreCase), "names should be quoted correctly");
         }
 
+
+        [TestMethod]
+        public void TestOracleWithCheckConstraint()
+        {
+
+            //arrange
+            var migration = new DdlGeneratorFactory(SqlType.Oracle).MigrationGenerator();
+            migration.EscapeNames = false;
+            migration.IncludeSchema = false;
+
+            var table = MigrationCommon.CreateTestTable("Orders");
+            table.SchemaOwner = "dbo";
+            table.CheckConstraints.Add(new DatabaseConstraint
+            {
+                Name = "COUNTRY_NN",
+                ConstraintType = ConstraintType.Check,
+                Expression = "\"COUNTRY\" IS NOT NULL"
+            });
+            var column = CreateNewColumn();
+            column.Nullable = false;
+
+            //act
+            var sql = migration.AddColumn(table, column);
+
+            //assert
+            Assert.IsTrue(sql.StartsWith("ALTER TABLE Orders ADD COUNTRY NVARCHAR2 (20) DEFAULT '' CONSTRAINT COUNTRY_NN NOT NULL", StringComparison.OrdinalIgnoreCase), "default constraint added");
+        }
+
         [TestMethod]
         public void TestMySqlWithSchema()
         {
diff --git a/DatabaseSchemaViewer/DatabaseSchemaViewer.csproj b/DatabaseSchemaViewer/DatabaseSchemaViewer.csproj
index c3ad5f91..29646e22 100644
--- a/DatabaseSchemaViewer/DatabaseSchemaViewer.csproj
+++ b/DatabaseSchemaViewer/DatabaseSchemaViewer.csproj
@@ -78,8 +78,8 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
-    <Reference Include="Oracle.ManagedDataAccess, Version=4.122.21.1, Culture=neutral, PublicKeyToken=89b483f429c47342, processorArchitecture=MSIL">
-      <HintPath>..\packages\Oracle.ManagedDataAccess.21.14.0\lib\net462\Oracle.ManagedDataAccess.dll</HintPath>
+    <Reference Include="Oracle.ManagedDataAccess, Version=4.122.23.1, Culture=neutral, PublicKeyToken=89b483f429c47342, processorArchitecture=MSIL">
+      <HintPath>..\packages\Oracle.ManagedDataAccess.23.6.0\lib\net472\Oracle.ManagedDataAccess.dll</HintPath>
     </Reference>
   </ItemGroup>
   <ItemGroup>
diff --git a/DatabaseSchemaViewer/app.config b/DatabaseSchemaViewer/app.config
index 00c05ac3..3ade4d44 100644
--- a/DatabaseSchemaViewer/app.config
+++ b/DatabaseSchemaViewer/app.config
@@ -65,7 +65,7 @@
     <DbProviderFactories>
       <remove invariant="Oracle.ManagedDataAccess.Client"/>
       <add name="ODP.NET, Managed Driver" invariant="Oracle.ManagedDataAccess.Client" description="Oracle Data Provider for .NET, Managed Driver"
-        type="Oracle.ManagedDataAccess.Client.OracleClientFactory, Oracle.ManagedDataAccess, Version=4.122.19.1, Culture=neutral, PublicKeyToken=89b483f429c47342"/>
+        type="Oracle.ManagedDataAccess.Client.OracleClientFactory, Oracle.ManagedDataAccess, Version=4.122.23.1, Culture=neutral, PublicKeyToken=89b483f429c47342"/>
     </DbProviderFactories>
   </system.data>
   <runtime>
@@ -73,7 +73,7 @@
       <dependentAssembly>
         <publisherPolicy apply="no"/>
         <assemblyIdentity name="Oracle.ManagedDataAccess" publicKeyToken="89b483f429c47342" culture="neutral"/>
-        <bindingRedirect oldVersion="4.121.0.0 - 4.65535.65535.65535" newVersion="4.122.19.1"/>
+        <bindingRedirect oldVersion="4.121.0.0 - 4.65535.65535.65535" newVersion="4.122.23.1"/>
       </dependentAssembly>
     </assemblyBinding>
   </runtime>
diff --git a/DatabaseSchemaViewer/packages.config b/DatabaseSchemaViewer/packages.config
index e7ff0e50..5d7f98f5 100644
--- a/DatabaseSchemaViewer/packages.config
+++ b/DatabaseSchemaViewer/packages.config
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="Oracle.ManagedDataAccess" version="21.14.0" targetFramework="net40" />
+  <package id="Oracle.ManagedDataAccess" version="23.6.0" targetFramework="net48" />
 </packages>
\ No newline at end of file