--- access_fix.sql	2002/02/22 17:28:19	1.1
+++ access_fix.sql	2002/02/22 17:46:58	1.2
@@ -1,3 +1,6 @@
+-- you will need this function if you are using row versioning
+-- according to http://odbc.postgresql.org/psqlodbc.php?DocID=faq-advanced#rowversioning you might not need it at all...
+
 drop function int4eq(xid,int4);
 drop operator = (xid,int4) ;
 
@@ -17,6 +20,8 @@
 );
 
 
+-- we need operators which can complare int and bool (because boolean type
+-- in Access are really integers when they finish thair way through optimizer
 
 DROP OPERATOR = (bool, int4);
 DROP OPERATOR = (int4, bool);
@@ -51,6 +56,7 @@
   JOIN = EQJOINSEL
 );
 
+-- this is reverse of above
 
 DROP FUNCTION MsAccessBool2 (int4, bool);
 CREATE FUNCTION MsAccessBool2 (int4, bool) RETURNS BOOL AS '
@@ -82,8 +88,12 @@
   JOIN = EQJOINSEL
 );
 
-DROP FUNCTION not (int4);
-CREATE FUNCTION not (int4) RETURNS BOOL AS '
+-- this is generaly not possible. However, when using boolean fields in
+-- PostgreSQL and Access you will need not on int type.
+-- so, if possible, rename this function to not
+
+DROP FUNCTION xnot (int4);
+CREATE FUNCTION xnot (int4) RETURNS BOOL AS '
 BEGIN
   IF $1 IS NULL THEN
     RETURN NULL;
