[Opensource] referencial integrity

[John Wooten]

Hi Stephen,

      For relational databases, the primary key of a record in one table
should tie to the foriegn key of a record in another table.  When you need
to delete a record from a database that enforces referential integrity, the
database will not let you perform the delete until you have removed the
record(s) whose foriegn key matches that of the primary key.  Otherwise you
would have "Orphan" records with no way to locate them.

Hope this helps.

John Wooten
Computer Sciences Corporation
jwooten3 at csc.com

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                      "Stephen Marron"                                                                                              
                      <stephenmarron           To:      <opensource at jcorporate.com>                                                 
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                      09/27/2003 09:27                                                                                              
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Hello,
My name is Stephen Marron.
I am currently studying at the Institute of Technology, Sligo, Ireland. I
am doing a degree in Web Development and as part of my course i am doing a
subject called Database Technology!
I am having trouble with this subject as i cannot understand the term
referencial integrity.

If at all possible could you define it for me in one or two lines in simple
terms which might make more sense to me.

Many Thanks.
Regards
Stephen Marron