Hmm.... two responses with exactly the same link... I am getting a message here. =) Thanks Wolfgang and Mark. Yes, Tanel's paper is awesome! Now I want to go sit in on his Advanced Troubleshooting seminars. *grin* Ok, I'll settle back and start reading some more. This is good stuff. On Thu, Apr 23, 2009 at 16:16, Wolfgang Breitling <breitliw@xxxxxxxxxxxxx>wrote: > How about Tanel (Poder)'s os_explain: > > http://blog.tanelpoder.com/2008/06/15/advanced-oracle-troubleshooting-guide-part-6-understanding-oracle-execution-plans-with-os_explain/ > > At 02:54 PM 4/23/2009, Charles Schultz wrote: > > After talking with some folks, it sounds like this functionality is not > even available at present, so there are no such tools that can take > advantage of it. > > Which got me to thinking. Hypothetically, how would this work? We know > Oracle builds a query plan for the purposes of being executed in a > particular fashion. Would it be a "trivial" matter of adding a stop check > flag (ie, breakpoint) to the existing code? I am thinking it would have to > be more complex than that, since the execution code must be optimized to run > extremely fast, and having a check for each operation could potentially be > expensive. > > I looked through Julian Dyke's most excellent "Internals" papers, but did > not find any detailed information about query execution internals. Has > anyone published anything along those lines? > > I blame Jonathan Lewis for getting me started down this track. *grin* His > copious contributions to the field, and the CBO in particular, are well > thought-out and extremely helpful, and his personality of always looking for > the truth is infectious. > > On Sat, Apr 18, 2009 at 21:55, Charles Schultz <sacrophyte@xxxxxxxxx> > wrote: > Good day, list, > > When I was taking a C++ class in college, for a short time we had access to > a really powerful X debugger (running on HPUX) that not only allowed one to > step through code but depicted the state of any watched objects (variables, > pointers, classes, etc) as a linked box with all relevant details > (addresses, values, members, etc). I really miss that tool. > > Is there anything related for stepping through SQL? Not PL/SQL, mind you. I > am looking for a tool that can show me, graphically, how access predicates > get rowids out of an index, which are then passed up to a table access with > a filter predicate, then passed into a nested loop operation as a driving > rowsource which dictates the rows wanted from the 2nd child operation. I > want to see data; which rows were gotten and why, one row at a time. I am > sure we have all see powerpoint slides that show us this detail one painful > click at a time, but what about a run-time tool? Direct memory attach > programs come to mind, but they usually do not cater to the same audience > for some strange reason (*grin*). The audiences I have in mind are in > classroom settings, teaching Jr. DBAs and developers; I doubt any > experienced DBA would admit to wanting something like this. But I do. =) > > PS - I did look around on google, but the hits were not promising. I was > not able to find much information about Visual SQL 4.2 (seems old), nor the > MS Visual Studio series - nothing in my quick driveby on the information > superhighway really satisfied me. > > -- > Charles Schultz > > > > > -- > Charles Schultz > Sent from Champaign, Illinois, United States > > Regards > > Wolfgang Breitling > Centrex Consulting Corporation > www.centrexcc.com > -- Charles Schultz Sent from Champaign, Illinois, United States