diff --git a/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/ServiceBufferFileStreamReader.cs b/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/ServiceBufferFileStreamReader.cs
index de22f564c7..0c1bc0406e 100644
--- a/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/ServiceBufferFileStreamReader.cs
+++ b/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/ServiceBufferFileStreamReader.cs
@@ -76,7 +76,7 @@ public ServiceBufferFileStreamReader(Stream stream, QueryExecutionSettings setti
                 {typeof(bool),           (o, id, col) => ReadBoolean(o, id)},
                 {typeof(double),         (o, id, col) => ReadDouble(o, id)},
                 {typeof(float),          (o, id, col) => ReadSingle(o, id)},
-                {typeof(decimal),        (o, id, col) => ReadDecimal(o, id)},
+                {typeof(decimal),        (o, id, col) => ReadSqlDecimal(o, id)},
                 {typeof(DateTime),       ReadDateTime},
                 {typeof(DateTimeOffset), (o, id, col) => ReadDateTimeOffset(o, id)},
                 {typeof(TimeSpan),       (o, id, col) => ReadTimeSpan(o, id)},
diff --git a/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/ServiceBufferFileStreamWriter.cs b/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/ServiceBufferFileStreamWriter.cs
index 522bdd5548..3267b6c90d 100644
--- a/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/ServiceBufferFileStreamWriter.cs
+++ b/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/ServiceBufferFileStreamWriter.cs
@@ -92,19 +92,19 @@ public ServiceBufferFileStreamWriter(Stream stream, QueryExecutionSettings setti
                 {typeof(byte[]), val => WriteBytes((byte[]) val)},
                 {typeof(Guid), val => WriteGuid((Guid) val)},
 
-                {typeof(SqlString), val => WriteNullable((SqlString) val, obj => WriteString((string) obj))},
-                {typeof(SqlInt16), val => WriteNullable((SqlInt16) val, obj => WriteInt16((short) obj))},
-                {typeof(SqlInt32), val => WriteNullable((SqlInt32) val, obj => WriteInt32((int) obj))},
-                {typeof(SqlInt64), val => WriteNullable((SqlInt64) val, obj => WriteInt64((long) obj)) },
-                {typeof(SqlByte), val => WriteNullable((SqlByte) val, obj => WriteByte((byte) obj)) },
-                {typeof(SqlBoolean), val => WriteNullable((SqlBoolean) val, obj => WriteBoolean((bool) obj)) },
-                {typeof(SqlDouble), val => WriteNullable((SqlDouble) val, obj => WriteDouble((double) obj)) },
-                {typeof(SqlSingle), val => WriteNullable((SqlSingle) val, obj => WriteSingle((float) obj)) },
+                {typeof(SqlString), val => WriteNullable((SqlString) val, obj => WriteString(((SqlString) obj).Value))},
+                {typeof(SqlInt16), val => WriteNullable((SqlInt16) val, obj => WriteInt16(((SqlInt16) obj).Value))},
+                {typeof(SqlInt32), val => WriteNullable((SqlInt32) val, obj => WriteInt32(((SqlInt32)obj).Value))},
+                {typeof(SqlInt64), val => WriteNullable((SqlInt64) val, obj => WriteInt64(((SqlInt64) obj).Value)) },
+                {typeof(SqlByte), val => WriteNullable((SqlByte) val, obj => WriteByte(((SqlByte) obj).Value)) },
+                {typeof(SqlBoolean), val => WriteNullable((SqlBoolean) val, obj => WriteBoolean(((SqlBoolean) obj).Value)) },
+                {typeof(SqlDouble), val => WriteNullable((SqlDouble) val, obj => WriteDouble(((SqlDouble) obj).Value)) },
+                {typeof(SqlSingle), val => WriteNullable((SqlSingle) val, obj => WriteSingle(((SqlSingle) obj).Value)) },
                 {typeof(SqlDecimal), val => WriteNullable((SqlDecimal) val, obj => WriteSqlDecimal((SqlDecimal) obj)) },
-                {typeof(SqlDateTime), val => WriteNullable((SqlDateTime) val, obj => WriteDateTime((DateTime) obj)) },
-                {typeof(SqlBytes), val => WriteNullable((SqlBytes) val, obj => WriteBytes((byte[]) obj)) },
-                {typeof(SqlBinary), val => WriteNullable((SqlBinary) val, obj => WriteBytes((byte[]) obj)) },
-                {typeof(SqlGuid), val => WriteNullable((SqlGuid) val, obj => WriteGuid((Guid) obj)) },
+                {typeof(SqlDateTime), val => WriteNullable((SqlDateTime) val, obj => WriteDateTime(((SqlDateTime) obj).Value)) },
+                {typeof(SqlBytes), val => WriteNullable((SqlBytes) val, obj => WriteBytes(((SqlBytes) obj).Value)) },
+                {typeof(SqlBinary), val => WriteNullable((SqlBinary) val, obj => WriteBytes(((SqlBinary) obj).Value)) },
+                {typeof(SqlGuid), val => WriteNullable((SqlGuid) val, obj => WriteGuid(((SqlGuid) obj).Value)) },
                 {typeof(SqlMoney), val => WriteNullable((SqlMoney) val, obj => WriteMoney((SqlMoney) obj)) }
             };
         }
@@ -299,7 +299,7 @@ internal int WriteChar(char val)
         internal int WriteBoolean(bool val)
         {
             byteBuffer[0] = 0x01; // length
-            byteBuffer[1] = (byte) (val ? 0x01 : 0x00);
+            byteBuffer[1] = (byte)(val ? 0x01 : 0x00);
             return FileUtilities.WriteWithLength(fileStream, byteBuffer, 2);
         }
 
diff --git a/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/StorageDataReader.cs b/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/StorageDataReader.cs
index 68742616b0..560e3209b7 100644
--- a/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/StorageDataReader.cs
+++ b/src/Microsoft.SqlTools.ServiceLayer/QueryExecution/DataStorage/StorageDataReader.cs
@@ -98,7 +98,7 @@ public Task<bool> ReadAsync(CancellationToken cancellationToken)
         /// <returns>The value of the given column</returns>
         public object GetValue(int i)
         {
-            return sqlDataReader == null ? DbDataReader.GetValue(i) : sqlDataReader.GetValue(i);
+            return sqlDataReader == null ? DbDataReader.GetValue(i) : sqlDataReader.GetSqlValue(i);
         }
 
         /// <summary>
@@ -113,7 +113,7 @@ public void GetValues(object[] values)
             }
             else
             {
-                sqlDataReader.GetValues(values);
+                sqlDataReader.GetSqlValues(values);
             }
         }
 
diff --git a/test/Microsoft.SqlTools.ServiceLayer.IntegrationTests/QueryExecution/DataStorage/StorageDataReaderTests.cs b/test/Microsoft.SqlTools.ServiceLayer.IntegrationTests/QueryExecution/DataStorage/StorageDataReaderTests.cs
index f5b3546205..e65fa5e7f7 100644
--- a/test/Microsoft.SqlTools.ServiceLayer.IntegrationTests/QueryExecution/DataStorage/StorageDataReaderTests.cs
+++ b/test/Microsoft.SqlTools.ServiceLayer.IntegrationTests/QueryExecution/DataStorage/StorageDataReaderTests.cs
@@ -44,6 +44,20 @@ public void GetBytesWithMaxCapacityTest()
             Assert.NotNull(bytes);
         }
 
+        /// <summary>
+        /// Validate GetBytesWithMaxCapacity
+        /// </summary>
+        [Test]
+        public void GetLongDecimalTest()
+        {
+            // SQL Server support up to 38 digits of decimal
+            var storageReader = GetTestStorageDataReader(
+                "SELECT 99999999999999999999999999999999999999");
+            storageReader.DbDataReader.Read();
+            var value = storageReader.GetValue(0);
+            Assert.AreEqual("99999999999999999999999999999999999999", value.ToString());
+        }
+
         /// <summary>
         /// Validate GetCharsWithMaxCapacity
         /// </summary>
@@ -63,7 +77,7 @@ public void GetCharsWithMaxCapacityTest()
             Assert.True(shortName.Length == 2);
 
             Assert.Throws<ArgumentOutOfRangeException>(() => storageReader.GetBytesWithMaxCapacity(0, 0));
-            Assert.Throws<ArgumentOutOfRangeException>(() => storageReader.GetCharsWithMaxCapacity(0, 0));     
+            Assert.Throws<ArgumentOutOfRangeException>(() => storageReader.GetCharsWithMaxCapacity(0, 0));
         }
 
         /// <summary>
@@ -94,10 +108,10 @@ public void StringWriterWithMaxCapacityTest()
             writer.Write(output);
             Assert.True(writer.ToString().Equals(output));
             writer.Write('.');
-            Assert.True(writer.ToString().Equals(output + '.'));       
+            Assert.True(writer.ToString().Equals(output + '.'));
             writer.Write(output);
             writer.Write('.');
             Assert.True(writer.ToString().Equals(output + '.'));
-        }       
+        }
     }
 }
\ No newline at end of file