On Wed, Aug 26, 2009 at 9:21 PM, danjenkins<jb2...@32k.com> wrote: > > Hello, > We use a julian.decimal format to represent date/time (i.e. noon of August > 26, 2009 would be 40049.5000) and we use this julian date for an index key. > Our databases are frequently up to 3GB in size containing 10 million records > with 15 assorted field types per record and contain 6 months of data. I'm > proposing to break up the julian.date into two separate integers for the > data and time and index off the date integer. > > Of course this change will give queries some sort of a speed boost, but by > how much would you think?
These kind of queries are asked often on the list, and they always puzzle me. At the most, one of the sql experts here can tell you whether or not a particular index will be used or how to better formulate a query, but when it comes to figuring out by how much would a particular query be faster by... well, you are the only one in this world best placed to answer that question. You know the hardware, the other processes running concurrently, you have the data. Just write a little benchmark program and measure it. That way you will have the most reliable answer. Anyone else's answer will just be pointless guesswork. Remember, assertions are politics... backing them up with evidence is science. .. -- Puneet Kishor http://www.punkish.org Carbon Model http://carbonmodel.org Charter Member, Open Source Geospatial Foundation http://www.osgeo.org Science Commons Fellow, http://sciencecommons.org/about/whoweare/kishor Nelson Institute, UW-Madison http://www.nelson.wisc.edu ----------------------------------------------------------------------- Assertions are politics; backing up assertions with evidence is science ======================================================================= Sent from Madison, WI, United States _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
