Yesterday, Alvaro Herrera committed patch written by Pavel Stehule which adds generate_subscripts(…) function.
English disclaimer: this post will be in Polish only, as it's use for other nationalities is somehow limited 🙂
Tom Lane committed his patch which modifies output of “EXPLAIN VERBOSE" command.
simple brainteaser. take no more than 30 seconds to think about it:
using standard cron installed on your unix system, how often would this command be run:
*/57 * * * * command
? if you choose to answer in comments, please supply version of cron that your system is using.
Quick note in polish: jeśli znasz moje poprzednie posty nt. drzew, to ten możesz sobie pewnie odpuścić. będzie zawierał jedynie opis implementacji zbliżony do tego co już jest dostępne.
OK, back to English (or at least my version of English).
Finding a good way to store trees in SQL was/is my long-term hobby. I tried ltree, basic adjacency list, Celko's nested sets way, and nothing really was able to make me feel satisfied.
Ltree is great, but PostgreSQL only (not that it's a big problem). Adjacency list is very simple in insert, update and delete operations, but forces me to use recursive queries in case of some not-so-standard queries. Nested sets are quite the contrary – great for selects, but I simply hate writing insert/update/delete to these trees.
Is there anything better? I think so.
as you perhaps know there is this site/blog called high scalability. it contains articles about various things related to performance, scalability, availability and so on.
usually, when there is something about databases, it is about mysql. luckily for us, today they showed something about postgresql:
unfrotunatelly i can't point you to message in archives, as there is some problem with them, and i dont see posts newer than “Fri Apr 04 12:00:08 2008".
this patch was written by tomas doran, and commited by bruce momjian: