Cherie - This is an OLTP application. I haven't received the schema yet. The performance goal is a good question, and I will ask it to the group when I find a good opportunity. Basically, they are looking for "reasonable" response times for on-line users. The development manager keeps saying that everything is still very preliminary, but they want to go ahead and create a schema so that they can start playing around with code. My cynical DBA side says that preliminary stuff tends to freeze in place pretty quickly. Basically, when you review a model, how many constraints on a table do you have to see to before you say "good grief, what a mess!". Or are there more critical points, like how many levels of table hierarchy, that are more important? Thanks for your questions, because you have given me more issues to consider. Dennis Williams DBA Lifetouch, Inc. [EMAIL PROTECTED]
-----Original Message----- Sent: Tuesday, January 22, 2002 6:46 AM To: Multiple recipients of list ORACLE-L Dennis, How many constraints are you talking about? About how many constraints per table? What kind of app is it? OLAP? Data Warehouse? What kind of performance requirements have been set? Cherie Machler Oracle DBA Gelco Information Network DENNIS WILLIAMS <DWILLIAMS@LIFE To: Multiple recipients of list ORACLE-L <[EMAIL PROTECTED]> TOUCH.COM> cc: Sent by: Subject: RE: Limits on referential integrity [EMAIL PROTECTED] m 01/21/02 04:35 PM Please respond to ORACLE-L Jared - I wasn't clear, but then again it is Monday. I have a team of inexperienced developers starting a big, new Java application. They have a good, experienced data model consultant helping them create the data model. They are eager to include referential integrity. So eager it has me a little worried. My question: "Is there too much of a good thing?". In Oracle 7, sometimes sites would remove RI to ensure good performance (we are starting this project on Oracle9i). Has anyone encountered problems with too many constraints? Any guidelines you use with developers? Thanks. Dennis Williams DBA Lifetouch, Inc. [EMAIL PROTECTED] -----Original Message----- Sent: Monday, January 21, 2002 4:16 PM To: Multiple recipients of list ORACLE-L I would be you lunch that what they are implementing in their code is not actually RI. They may be implementing code to ensure things get inserted in the right order, and that child rows have a parent. This is a very weak form of RI. Oracle is very good at implementing RI, and it is not dependent on an application. RI in the database is the route to choose unless there is some good reason not to. RI in the database will prevent orphaned data created through updates, deletes or even ( gasp! ) bugs in the app. Programmers tend to dislike RI in the database because it forces them to maintain data integrity in a transaction. This is not a bad thing, it just forces them to have a good understanding of their transactions. Point out to them that it is less code to write as well. :) Jared DENNIS WILLIAMS <[EMAIL PROTECTED]> Sent by: [EMAIL PROTECTED] 01/21/02 01:35 PM Please respond to ORACLE-L To: Multiple recipients of list ORACLE-L <[EMAIL PROTECTED]> cc: Subject: Limits on referential integrity How much referential integrity should be implemented in Oracle? We are starting a large new Java project. Our current applications keep their referential integrity inside their own dictionary, so I haven't had to deal much with referential integrity recently. Can there be too much of a good thing? What guidelines do you tend to use? At this point the developers are designing the data model so they are busily linking all the little boxes. My attitude at this point is "implement what you've got and if there are performance problems we'll deal with them when they arise". Can anyone give me a better motto? Thanks. Dennis Williams DBA Lifetouch, Inc. [EMAIL PROTECTED] -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).