diff --git a/product/roundhouse.databases.oracle/OracleDatabase.cs b/product/roundhouse.databases.oracle/OracleDatabase.cs
index f2df4ad2..b2924f21 100644
--- a/product/roundhouse.databases.oracle/OracleDatabase.cs
+++ b/product/roundhouse.databases.oracle/OracleDatabase.cs
@@ -172,7 +172,7 @@ private IParameter<IDbDataParameter> create_parameter(string name, DbType type,
             parameter.Direction = ParameterDirection.Input;
             parameter.ParameterName = name;
             parameter.DbType = type;
-            parameter.Value = value;
+            parameter.Value = value ?? DBNull.Value;
             if (size != null)
             {
                 parameter.Size = size.Value;