When dealing with several tables at once—especially large ones—tuning queries, tables, and geometries becomes a major consideration. The way you express your queries is also important because the same logic expressed with two different SQL statements can have vastly different performance. The complexity of geometries, memory allocation, and even storage affect performance.
Stay tuned for our next book pgRouting: A Practical Guide published by Locate Press due out in hard-copy 4th quarter 2017. Content is now feature complete and can purchase e-Book draft and get final when goes to print.
© Leo Hsu and Regina Obe 2014