Performance tag groups posts regarding software performance issues and the best practices on solving and monitoring performance issues.
In terms of general through-put design and long term support, I'm considering what would be a "best approach" for needing to create multiple batch files in a few different layouts from the same data-sets.
I need to iterate over a few very large tables to generate consistent batch outputs for different partner applications that need to be working on the same "version" of the source data.
Online document says: TUNE TABLE updates the SQL table definition (and therefore requires privileges to alter the table definition). Commonly, TUNE TABLE also updates the corresponding persistent class definition. This allows the gathered statistics to be used by the query optimizer without requiring a class compilation.
I don't get the point. If I run tune table once with class update and next time no class update, does this cause inconsistce of sql definition and class definition? What happen if I recompile the class ?