2009年3月19日星期四

greasemonkey should have scripts for gmail inline HTML editor

select spid from v$process where addr=(select distinct paddr from v$session natural join v$mystat)

select distinct spid from v$process natural join (select paddr addr from v$session natural join v$mystat)

both works to tell the server process id, but i love the 2nd, for natural join is cool:)
so the plan below is for the 2nd version, which has the same cost as 1st version.
and i noticed the sort merge join :)

Id_Operation Name RowsBytesCost (%CPU)Time
0_SELECT STATEMENT
11851 (100)00:00:01
1__HASH UNIQUE
11851 (100)00:00:01
2___NESTED LOOPS
11850 (0) 00:00:01
3____NESTED LOOPS
1172 0 (0)00:00:01
4_____MERGE JOIN CARTESIAN
11030 (0)00:00:01
* 5______FIXED TABLE FULL X$KSUMYSTA 1650 (0)00:00:01
6_______FIXED TABLE FULL X$KSUSGIF 10013000 (0)00:00:01
7______BUFFER SORT
1380 (0)00:00:01
* 8_______FIXED TABLE FULL X$KSUPR 1380 (0)00:00:01
* 9_____FIXED TABLE FIXED INDEX X$KSUSE (ind:1) 1690 (0)00:00:01
* 10____FIXED TABLE FIXED INDEX X$KSLED (ind:2) 1130 (0)00:00:01

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