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how Oracle execute this
I have an example:
SQL> SELECT COUNT(*) FROM DUMMY_VW;
COUNT(*)
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10000
SQL> SELECT COUNT(*) DUMMY_VW
2 WHERE TAX_ID='END';
COUNT(*)
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1
THE QUESTIONS IS: on the second query, does the view query 10000 rows and filter the one specified values by the "WHERE" clause, or does it parse out from the select ????
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the optimizer will look at the definition of the dummy_vw view (i'm guessing that is what it is) and look for the lowest cost access path for returning the correct result.
Read the concepts guide.
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Reminds me of an OCP question...
What is the order Oracle processes a select statement.
1) FROM
2) WHERE
3) SELECT
4) ORDER BY
In other words, FROM xxx, WHERE this is true, SELECT this data, and then sort it.
MH
I remember when this place was cool.
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That OCP certainly hones a person's knowledge to a keen edge, what?
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