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Wednesday, May 10, 2006

NewBee Trigger Question

SQL Apprentice Question
I want to create a basic insert trigger. In T1 I add a row, which creates a
new ID. The trigger fires after the insert, how do I get the new ID to add
to the child table?

I know this is as simple as it gets but I've read about 10 posts and dont'
see it?


Thanks in advance.

Celko Answers
>> want to create a basic insert trigger. In T1 I add a row, which creates a new ID [sic]. The trigger fires after the insert, how do I get the new ID to add to the child [sic] table? <<


Stop using SQL and go back to a network database. You have described
how they work as they build pointer chains as the data is inserted. I
am not kidding -- read a DB history book. You even used the term
"child" instead of "referenced" table!! Pure network/pointer chain
database concepts and terms, not anything like RDBMS.


>> I've read about 10 posts and dont' see it? <<


Perhaps you should have read one book on RDBMS instead?

You do not create a relational key. It already exists in the real
world and you discover it.


Triggers are a kludge for putting procedural code into a declarative
language.


You need to start over; you do not know what you are doing. People
here will give you kludges to get rid of you quickly because we cannot
give you a 1-2 year course in RDBMS. Telling someone to "smash rats
with a rock when they get near your baby" is easier than "improve the
sewer system by learning civil engineering so rats are not a problem"


Look up this article: http://www.apa.org/journals/psp/psp7761121.html


Journal of Personality and Social Psychology


Unskilled and Unaware of It: How Difficulties in Recognizing One's Own
Incompetence Lead to Inflated Self-Assessments


Remember it takes SIX years to become a Union Journeyman Carpenter in
New York State. How many years to be an SQL programmer? A few weeks
in a ceritificate training class!

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