Are Sql functions different from user defined functions ?

Hello,
SQL functions are built into Oracle Database and are available for use in various appropriate SQL statements. Do not >confuse SQL functions with user-defined functions written in PL/SQL.according to first paragraph of this document Sql functions are different from user defined functions . How is that ?
Is they really differ from each other ?

bootstrap wrote:
If you don't know what compilation is, please use Wikipedia or other online resources.I know what is compilation . But i was confused whether those sql functions are compiled in my machine when i install Oracle Database in my machine or they are pre-compiled .
As you said these Sql functions are pre-compiled , it is clear now that they are pre-compiled platform dependent code .
Can you provide actual source code of any SQL function , say SUM function .
I want to see it, how they have defined . Eagerly waiting for any reply. please help .
Edited by: bootstrap on Aug 19, 2011 11:50 AMYou can ask oracle if they give you their code. I doubt they will. However if you want to write you own user-defined aggregation function, there are examples in the documentation how to do that.
http://download.oracle.com/docs/cd/E11882_01/appdev.112/e17125/adfns_packages.htm#i1008575
Edited by: Sven W. on Aug 19, 2011 9:24 AM

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============================
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Post Author: JoannKarp
CA Forum: Formula
Is it possible to use a user defined function in SQL and use this in multiple Crystal reports?
JoannKarp

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Ricky

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Are Sql functions different from user defined functions ?

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