On 25/08/09 6:23 PM, Null kühl wrote:
> 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 ?
It will depend on what you are doing. But I think you should explore 'paging' in Cayenne before your current approach. Only once you find you actually have performance problems should you go down this path. You will no longer be able to deal with clients as a list of Client objects which means no validation, saving data back to the db, and much more which Cayenne gives you.
It is a common mistake of people new to ORMs to still think in terms of SQL and reading columns. Perhaps in your case this is necessary to get the speed you want, but often it is a premature optimisation which precludes a lot of useful functionality.
Ari Maniatis
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Aristedes Maniatis
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