diff --git a/utils/dbmaint.q b/utils/dbmaint.q
index d00d97c..3944512 100644
--- a/utils/dbmaint.q
+++ b/utils/dbmaint.q
@@ -66,7 +66,10 @@ reordercols0:{[tabledir;neworder]
 rename1col:{[tabledir;oldname;newname]
  if[(oldname in ac)and not newname in ac:allcols tabledir;
   stdout"renaming ",(string oldname)," to ",(string newname)," in `",string tabledir;
-  .os.ren[` sv tabledir,oldname;` sv tabledir,newname];@[tabledir;`.d;:;.[ac;where ac=oldname;:;newname]]]}
+  .os.ren[` sv tabledir,oldname;` sv tabledir,newname];
+  if[not ()~key ` sv tabledir,oldname1:`$(string oldname),"#";
+   .os.ren[` sv tabledir,oldname1;` sv tabledir,`$(string newname),"#"]];
+  @[tabledir;`.d;:;.[ac;where ac=oldname;:;newname]]]}
 
 ren1table:{[old;new]stdout"renaming ",(string old)," to ",string new;.os.ren[old;new];}