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jsze · 10-06-2004, 05:13 PM

Hi Technoboard,

I am not much of a database lingo person, but I'll try to answer your question.

If the query was written like this:

select col_id, col_a, col_b, col_x, ... col_n
from table_1 t1, table_2 t2, ...
where t1.col_id = t2.col_id and ...

Even with indexes created, it takes a noticeable longer time to retrieve the rows (for my case).

I looked up for some info online, and found out that the scalar subquery (select within a select) is an improvement in Oracle 8i/9i and above, to enable faster and smarter row retrieval:

http://www.dba-oracle.com/art_9i_scalar_subq.htm

Hope this answers your question.

10-06-2004, 05:13 PM	#5 (permalink)
jsze Registered User Join Date: Oct 2004 Posts: 3	Hi Technoboard, I am not much of a database lingo person, but I'll try to answer your question. If the query was written like this: select col_id, col_a, col_b, col_x, ... col_n from table_1 t1, table_2 t2, ... where t1.col_id = t2.col_id and ... Even with indexes created, it takes a noticeable longer time to retrieve the rows (for my case). I looked up for some info online, and found out that the scalar subquery (select within a select) is an improvement in Oracle 8i/9i and above, to enable faster and smarter row retrieval: http://www.dba-oracle.com/art_9i_scalar_subq.htm Hope this answers your question.