2026-03-12 20:23:15

tpt/bclass.sql

@@ -0,0 +1,22 @@
+-- Copyright 2018 Tanel Poder. All rights reserved. More info at http://tanelpoder.com
+-- Licensed under the Apache License, Version 2.0. See LICENSE.txt for terms & conditions.
+
+-- blcass.sql by Tanel Poder (http://blog.tanelpoder.com)
+--
+-- Usage: @bclass <block_class#>
+
+--with undostart as (select r from (select rownum r, class from v$waitstat) where class = 'undo header')
+
+select class, r undo_segment_id from (
+    select class, null r
+    from (select class, rownum r from v$waitstat) 
+    where r = bitand(&1,to_number('FFFF','XXXX'))
+    union all
+    select 
+        decode(mod(bitand(&1,to_number('FFFF','XXXX')) - 17,2),0,'undo header',1,'undo data', 'error') type 
+      , trunc((bitand(&1,to_number('FFFF','XXXX')) - 17)/2) undoseg_id
+    from 
+        dual
+)
+where rownum = 1
+/