how Oracle execute this
I have an example:
SQL> SELECT COUNT(*) FROM DUMMY_VW;
SQL> SELECT COUNT(*) DUMMY_VW
2 WHERE TAX_ID='END';
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 ????
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.
Reminds me of an OCP question...
What is the order Oracle processes a select statement.
4) ORDER BY
In other words, FROM xxx, WHERE this is true, SELECT this data, and then sort it.
I remember when this place was cool.
That OCP certainly hones a person's knowledge to a keen edge, what?
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