What is the disadvantage of using hints in query

hi all,
i am report developer, in my project we were using hits in the query ... so that the query performance has improved ..
my question is if we use hints in the query will it give any effects.. means to say instead of using hints we can make use of execution plan..
what is the use of execution plan i don't know.. but i have an ideal about it .. if we change the execution plan then that will be use full i think
please reply me,, if am wrong please correct me.. am not that much good at execution plan and hints in oracle..
please tel me the difference between hints and execution plan and which one is better ?
Thanks
Raja

Hint are used to bias the execution plan of a query. So there is no 'which is bettter'. Hints may be used to generate a different execution plan, but you can't predict how an execution plan looks like in the end. This decision is done by the db engine.
It best to start without any hints and let the query optimizer do the work. For queries you feel run to slow you can try to give hints and see if your assumption is correct (when the execution time is faster with hints).
On the other side your question is not related to jdev. You may ask the question in the {forum:id=75} forum
Timo

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