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MySql Question

ShoulderChip · 2009-02-22 16:53:47

Is it possible to produce a derived record from a table. I have a course table it contains a filed which represents the max no. of participants. I need a field to tell me how many places are left It could easily do this by returning the th emax number minus the total record-count. but can I create a derived record to throw…

22-02-2009 4:53pm

#1

ShoulderChip

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Is it possible to produce a derived record from a table.
I have a course table
it contains a filed which represents the max no. of participants.

I need a field to tell me how many places are left

It could easily do this by returning the th emax number minus the total record-count.
but can I create a derived record to throw this value into a table.

thank you.

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Comments

#2 22-02-2009 5:35pm

Creamy Goodness

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Posts: 25713

you could do it with the use of triggers. so everytime someone signs up for a course the number of places left gets decremented by one.

http://dev.mysql.com/doc/refman/5.0/en/triggers.html

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