Re: Simple Select Query

From: Null kühl (null.kuh..mail.com)
Date: Tue Aug 25 2009 - 04:23:02 EDT

  • Next message: Andrey Razumovsky: "Re: Simple Select Query"

    yes, but imagine if it's a huge table, performance wise, ill be reading the
    whole table from the db, all columns and all rows.then throw away all the
    data except for a certain column, would it have a vast effect on performance
    if i just constrain the reading from the beginning ?

    On Tue, Aug 25, 2009 at 10:20 AM, Aristedes Maniatis <ar..aniatis.org>wrote:

    > On 25/08/09 5:29 PM, Null kühl wrote:
    >
    >> also the return of such a query will be a list of clients as List<clients>
    >> c; , or since am querying for a certain field it can be something like
    >> List
    >> <String> names;
    >>
    >
    > Although you can do what you want by returning DataRows, I strongly advise
    > you avoid that approach while you are learning Cayenne. Instead, just
    > perform the query to return full objects. The whole point of Cayenne is so
    > that you can stop worrying about columns and start thinking in terms of Java
    > objects.
    >
    > Ari Maniatis
    >
    > -------------------------->
    > Aristedes Maniatis
    > GPG fingerprint CBFB 84B4 738D 4E87 5E5C 5EFA EF6A 7D2E 3E49 102A
    >



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