2026-03-12 20:23:15

tpt/demos/predicate_ordering.sql

@@ -0,0 +1,42 @@
+-- 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.
+
+drop table t;
+
+set echo on
+
+create or replace function f(x in number) return number as
+begin
+   dbms_output.put_line('F='||to_char(x));
+   return x;
+end;
+/
+
+set serverout on size 1000000
+
+select * from dual
+where 
+   rownum = f(2)
+or rownum = f(1)
+/
+
+create table t (a, b) as select 1, 1 from dual connect by level <= 100000;
+insert into t values (1,2);
+commit;
+
+@gts t
+
+truncate table t;
+insert into t values (1,2);
+commit;
+
+--exec dbms_stats.set_table_stats(user, 'T', numrows=>1000000, numblks=>10000, avgrlen=>10, no_invalidate=>false);
+
+select * from t where b=f(2) or a=f(1);
+
+set echo off serverout off
+
+/
+
+@x
+