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Re: getting the results of a sub select
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Re: getting the results of a sub select


  • Subject: Re: getting the results of a sub select
  • From: Arturo Perez <email@hidden>
  • Date: Tue, 15 Mar 2005 08:44:37 -0500

Ken Anderson wrote:

Ted,

You need to think of jobs and clients as objects that have relationships to each other. If you continue to think about things in terms of SQL and specialized queries, you're going to have a hard time with EOF (the database layer of WebObjects).

This can not be emphasized enough. If you can stop thinking about the SQL and just concentrate on what you need to do you will avoid a lot of frustration. EOModeler can be very helpful in this respect. For a neophyte WO person just let EOF do what it wants. When it can't do something or you're tempted to change how EOF has defined something come check with this list first. Otherwise you'll be in for a world of hurt.


One thing that's important to realize here is that, by default, EOF will make a trip to the database for each client you need to fetch. If you're displaying client.cname in a table or something, that can become very inefficient.

Just to clarify this section as it sounds as if EOF will fetch each attribute of an object one at a time. EOF will fetch the entire object and all its attributes. However, for relationships, EOF will place a fault in the object as a stand-in to avoid joins & the possibility of loading hundreds of objects when you only need one.


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References: 
 >getting the results of a sub select (From: Theodore Petrosky <email@hidden>)
 >Re: getting the results of a sub select (From: Ken Anderson <email@hidden>)

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