Hi, Given I have a large table implemented with partitions and need fast access to a (primary) key value in a scenario where every minute updates (inserts/updates/deletes) are coming in.
Now since PG does not allow any index (nor constraint) on "master" table, I have a performance issue (and a possible parallelization opportunity). Say, there is a table with 250 mio. rows split into 250 tables with 1 mio. rows each. And say the the index behavior is O(log n). Then a search for a key takes O(log(250*n)) or 8.4 time units. What PG (9.1) currently probably does is a iterative call to all 250 partitioned tables, which will take O(250*log(n)) - or 1500 time units in this case. This is about 180 times slower. What do you think about introducing a "global index" over all partitions (like Ora :->)? This would be a (logically) single index which can be even be parallelized given the partitioned tables are optimally distributed like in different tablespaces. What do you think about this? -S. -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
