(repost) Is the "Global Optimizer Statistics" section unreliable in a SQL Anywhere 17.0.10.5745 Graphical Plan With Statistics? Should that section be ignored? In particular, why does it say "Optimization goal All-rows" when all evidence, including the plan's own "Optimizer Statistics" section, says "optimization_goal First-row"? This is critically important when it comes to debugging performance problems. Here are some details... ===== Graphical Plan top SELECT node Advanced Details tab Global Optimizer Statistics Optimization goal All-rows FALSE? ===== top SELECT node Details tab Optimizer Statistics section optimization_goal First-row TRUE? ProductVersion 17.0.10.5745 ===== reload.sql SET OPTION "PUBLIC"."optimization_goal"='Response-time' ===== Foxhound Display Schema SET OPTION PUBLIC.optimization_goal = 'Response-time'; -- different from default 'All-rows' Note: For a TL;DR discussion of 'Response-time' === 'First-row' see this post: Database option optimization_goal value after upgrading database from version 9 to 17 |