PreparedStatement - Any Good If I Close?

Question

The benefit of using PreparedStament and Bind Variable is it's performance if used multiple times. As it doesn't go through the compilation/parsing, the plan is already there as well as the structure is available. Now if I close the statement, does that mean I loose the reference and I've to go through the same steps each time.
So using PreparedStament doesn't provide any help if I close?
Pls elaborate.. Thanks a lot.

Answer 1

if you close them,closing is just for returning the
resource to database. when you use
conn.prepareStatement("xyz") the sql will besearched
from the library cache from the shared pool by dband
no reparsing will occur.Not necessarily. Actually I am not sure that that
ever occurs, although it might. That is why one keeps
the preparedStatement around, so the resource is not
permanently lost.In case of Oracle:
When you send a sql statement to db,it makes an exact match seach in library cache of shared pool where it stores sql string and its compiled information together with execution plan..etc
When you use PreparedStatement you use bind variables i.e select * from A where c=?
when you use statement you use
select * from A where c=1,select * from A where c=2,select * from A where c=3..
where all these are different sql strings and an exact match is not found in library cache.
In case of PreparedStatments since ? is used for places where changes occur,exact matches are obtained so database doesn't need to reparse and recompile the sql string.