diff --git a/lazarus/dbconstants.pas b/lazarus/dbconstants.pas
index 7bbe344..2b24675 100644
--- a/lazarus/dbconstants.pas
+++ b/lazarus/dbconstants.pas
@@ -5,7 +5,7 @@
 interface
 
 const
-  SQLNull = -1;
+  SQLNull = -693594;
 
 implementation