----------------------------------------------------------------------- WORKLOG TASK -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- TASK...........: Encapsulate calculations of the table access cost and make them consistent and tunable CREATION DATE..: Mon, 16 Apr 2012, 18:32 SUPERVISOR.....: IMPLEMENTOR....: COPIES TO......: Igor Knielsen Monty Psergey Sanja Sergei Timour Wlad CATEGORY.......: Server-Sprint TASK ID........: 251 (http://askmonty.org/worklog/?tid=251) VERSION........: Benchmarks-3.0 STATUS.........: Assigned PRIORITY.......: 60 WORKED HOURS...: 0 ESTIMATE.......: 0 (hours remain) ORIG. ESTIMATE.: 0 PROGRESS NOTES: DESCRIPTION: This task is mostly a re-engineering task. Currently when calculating the cost of a ref table access method the function best_access_path makes an assumption that any index look-up is performed into a B-tree and the function uses engine independent code for this calculations. The cost calculations also use some constants that should be done tunable through system variables since these constants may be different for different platform/environments. This task is implemented in preparation for the development that will support more realistic cost model for query execution plans. ESTIMATED WORK TIME ESTIMATED COMPLETION DATE ----------------------------------------------------------------------- WorkLog (v4.0.0)