Index: openacs-4/packages/xowiki/tcl/upgrade/upgrade.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/tcl/upgrade/upgrade.tcl,v
diff -u -r1.15.2.14 -r1.15.2.15
--- openacs-4/packages/xowiki/tcl/upgrade/upgrade.tcl	16 Sep 2021 09:49:47 -0000	1.15.2.14
+++ openacs-4/packages/xowiki/tcl/upgrade/upgrade.tcl	13 Jun 2022 16:50:33 -0000	1.15.2.15
@@ -901,6 +901,24 @@
         ns_log notice "Modified prototype pages for $page: $item_ids (require manual checking)"
       }
     }
+
+    set v 5.10.1d31
+    if {[apm_version_names_compare $from_version_name $v] == -1 &&
+        [apm_version_names_compare $to_version_name $v] > -1} {
+      ns_log notice "-- upgrading to $v"
+
+      if {[::xo::dc 0or1row constraint_exists {
+        SELECT 1 FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS
+        WHERE CONSTRAINT_NAME ='xowiki_page_instance_page_template_fkey'
+        AND TABLE_NAME = 'xowiki_page_instance'}]} {
+        ::xo::dc transaction {
+          ::xo::dc dml drop_constraint \
+              "alter table xowiki_page_instance drop constraint xowiki_page_instance_page_template_fkey"
+          ::xo::dc dml recreate_constraint \
+              "alter table xowiki_page_instance add constraint xowiki_page_instance_page_template_fkey foreign key (page_template) references cr_items(item_id)"
+        }
+      }
+    }
   }
 }