RE: JDBC driver for MySQL or... - Terrence W. Zellers - com.mysql.lists.java

10 messages in com.mysql.lists.javaRE: JDBC driver for MySQL or...

From	Sent On	Attachments
Ross Lambert	06 Dec 2000 12:14
Terrence W. Zellers	06 Dec 2000 12:34
Ross Lambert	06 Dec 2000 13:03
Mark Matthews	06 Dec 2000 13:36
Vinny	06 Dec 2000 14:24
Ross Lambert	06 Dec 2000 15:05
Krishnan Srinivasan	06 Dec 2000 20:49
Brian Davidson	07 Dec 2000 06:49
Ross Lambert	07 Dec 2000 08:41
Terrence W. Zellers	07 Dec 2000 08:49

Subject:	RE: JDBC driver for MySQL or...
From:	Terrence W. Zellers (zell...@voicenet.com)
Date:	12/07/2000 08:49:24 AM
List:	com.mysql.lists.java

On Thu, 7 Dec 2000, Ross Lambert wrote:

Brian,

In case performance is an issue, we use LIMIT to control our page flows also but have found that going from 500 to 600 (for example) takes as long as 0 to 600.

Yes, performance is a huge issue and your observation was confirmed off-list. Someone suggested via e-mail that I take the original query

If you use LIMIT, yes in the server you still create the entire result as if there had been no limit specified - or at least to the tail of your limit request [which will necessarily be all if there is an ORDER specified whether explicitly or implicitly].

BUT by using LIMIT you circumscribe the amount of data which must be received and interpreted by your applet; not using LIMIT would require the entire unlimited query to be cached and stored in the applet's memory space with all the communication, some byte-by-byte decoding and object creation/instantiation required at for each row. With limit you require only to receive and instantiate the objects representing the data you are actually interested in. If you are at all concerned about performance superfluous object creation in the JVM is a big no-no.

-- TWZ