| Using aliases to improve performance? [message #372298] |
Wed, 31 January 2001 15:48  |
Gerald
Messages: 54
Registered: January 2001
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Member |
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Hi all,
I'm taking a Report Builder CBT and am creating a query. The CBT states that "Table aliases help your query to access the database and return data as quickly as possible". I find this difficult to believe. Can someone explain?
thanks,
Gerald
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| Re: Using aliases to improve performance? [message #372301 is a reply to message #372298] |
Wed, 31 January 2001 19:55  |
Andrew again...
Messages: 270
Registered: July 2000
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Senior Member |
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In simple terms, parsing the query in marginally quicker as you implicitly specify which tables columns belong to.
i.e. select d.dept_name, e.emp_name
from dept d, emp e
where...
Oracle does not need to determine which table dept_no etc belong to.
Execution should be completely unaffected. As running reports consume minimal time parsing the statement, I doubt that you will ever see an improvement - but every bit helps :)
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