Sorry, I should have mentioned that the app doesn't allow NULLs, even though
there's no constraint on that column.  The column is type CHAR.  The
:old.commodity_code check in the WHEN clause is there to account for
INSERTed rows.  The table has about 200K rows total (inventory part master),
with only 1-to-10 rows inserted per day normally.  Many 1000s of UPDATEs per
day, potentially, yes.

Thanks,
Rich

Rich Jesse                           System/Database Administrator
[EMAIL PROTECTED]                  Quad/Tech Inc, Sussex, WI USA



-----Original Message-----
Sent: Wednesday, July 30, 2003 2:20 PM
To: Multiple recipients of list ORACLE-L


the trigger will fire if :new.commodity_code is null as well ... 
Raj 
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Rajendra dot Jamadagni at nospamespn dot com 
All Views expressed in this email are strictly personal. 
QOTD: Any clod can have facts, having an opinion is an art ! 


-----Original Message----- 
Sent: Wednesday, July 30, 2003 3:10 PM 
To: Multiple recipients of list ORACLE-L 


Since I'm getting nowhere fast with Oracle Support, I'll try this here: 
While looking in V$DB_OBJECT_CACHE, we noticed an unpinned row-level trigger

had been fired over 900K times. We compared this to other row-level triggers

on the same table and noticed that the other triggers were only executed 
around 
1000 or 2000 times. From knowledge of the business, it would seem that the 
latter is much more believable. The major difference between this trigger 
and 
the others is that the others all have a column declared in the FOR UPDATE 
clause of the trigger. For example, here's the header of the trigger in 
question: 
CREATE OR REPLACE TRIGGER QT_BLAH_BLAH_IU 
AFTER INSERT OR UPDATE ON my_table 
FOR EACH ROW 
WHEN (NEW.commodity_code != OLD.commodity_code OR OLD.commodity_code IS 
NULL) 
...while the other triggers would also contain an "OF my_column" clause 
immediately following "AFTER INSERT OR UPDATE". 
The table contains about 200K rows. Having this trigger fire 900K times is 
highly unlikely, given the WHEN clause.  According to Oracle8i Application 
Developer's Guide - Fundamentals, about the WHEN clause of a row-level 
trigger: 
"If the expression evaluates to TRUE for a row, then the trigger body is 
fired 
on behalf of that row. However, if the expression evaluates to FALSE or NOT 
TRUE for a row (unknown, as with nulls), then the trigger body is not fired 
for 
that row." 
The same manual also says: 
"If a triggering statement specifies UPDATE, then an optional list of 
columns 
can be included in the triggering statement. If you include a column list, 
then 
the trigger is fired on an UPDATE statement only when one of the specified 
columns is updated. If you omit a column list, then the trigger is fired 
when 
any column of the associated table is updated." 
This leaves me a little confused as to what exactly fires when with a 
trigger. 
I know that bug 1764313 says the execution count is inaccurate, but if 
anything 
that bug would suggest that the 900K rows is LOW and not HIGH like we've 
seen. 
I guess my real question is what part of a trigger is loaded when. Is there 
a 
difference between the trigger and the trigger body when it comes to 
executions?  How is this difference shown the V$DB_OBJECT_CACHE or V$SQLAREA

for that matter?  Is the distinction similar to PACKAGE vs. PACKAGE BODY? 
BTW, if it matters, we're currently on 32-bit 8.1.7.4.0 on 64-bit HP/UX 
11.0. 
TIA, 
Rich 
Rich Jesse                           System/Database Administrator 
[EMAIL PROTECTED]                  Quad/Tech Inc, Sussex, WI USA 
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