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inner / sub / inline query

 
aakash bhatt
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What is the diff between inner query / sub query / inline query
Regards,
aakash
 
Mark Spritzler
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I might get this wrong, but a subquery is usually in the From clause, and an inline query is in the Select portion of a query. Haven't heard something be called an inner query though.
Mark
 
yogesh sood
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hi there,
Lets start with Inline View or rather inline query...
take a look at example:-
/*
Select ename,sal from (select ename,sal from emp order by) where rownum < 5.
*/
here after from there is no table name it is the result of query that is being used this is called inline view or inline query.
anyone can throw some light on Sub queries not sure im confident in that
 
Rudy Dakota
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Hi there,
A subquery as I know it is part of the where clause. A simple example:

As might be obvious most, if not all, subqueries can be reformulated to be simply joins (rather obvious in this example). That is also what a decent optimizer would do.
Subqueries do have a use in keeping your SQL readable, certainly when the statements get more complex, I 'd say.
Good riddance,
Rudy.
 
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