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maximum value

 
Manuel Paco
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Help please
What is the fastest way to get the maximum value in the field.
I need to get this value to my variable and use it as a base for deriving my invoice number.
 
Tina Coleman
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Fastest way? Use an AUTONUMBER field in something like Oracle or MySQL - let it get the next number, and then build your invoice number off of it. Alternatively,

Make sure you synchronize invoice number creation/usage so that you don't reuse your number (or have some other scheme for unique invoice number creation - using a unique key on invoice number is typical, to validate that created numbers are unique).
Depending on your database/enterprise architecture, you could theoretically also write a trigger that creates the invoice number upon insert of a record. The advantage there is that you know everyone inserting a record is using the same algorithm for creating an invoice number.
 
Manuel Paco
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Thank you.
Select MAX(number) from . . .
How do I get value from that?
 
Manuel Paco
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I got it. Works. Thanks.
 
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