Index: openacs-4/packages/xotcl-core/tcl/05-db-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-core/tcl/05-db-procs.tcl,v
diff -u -N -r1.148.2.24 -r1.148.2.25
--- openacs-4/packages/xotcl-core/tcl/05-db-procs.tcl	6 Aug 2020 12:44:56 -0000	1.148.2.24
+++ openacs-4/packages/xotcl-core/tcl/05-db-procs.tcl	1 Sep 2020 17:59:34 -0000	1.148.2.25
@@ -937,9 +937,13 @@
   } {
     if {[db_driverkey ""] eq "oracle"} {
       set name [string toupper $name]
-      if {[::xo::dc 0or1row exists "
-         SELECT 1 FROM user_sequences
-          WHERE sequence_name = :name limit 1"]} return
+      if {[::xo::dc 0or1row exists {
+        select case when exists
+         (SELECT 1 FROM user_sequences
+           WHERE sequence_name = :name)
+        then 1 else 0 end
+        from dual
+      }]} return
     } else {
       #
       # PostgreSQL could avoid this check and use 'if not exists' in