On Thu, Sep 8, 2016 at 12:32 AM, Amit Kapila <amit.kapil...@gmail.com> wrote: > Hmm. I think page or block is a concept of database systems and > buckets is a general concept used in hashing technology. I think the > difference is that there are primary buckets and overflow buckets. I > have checked how they are referred in one of the wiki pages , > search for overflow on that wiki page. Now, I think we shouldn't be > inconsistent in using them. I will change to make it same if I find > any inconsistency based on what you or other people think is the > better way to refer overflow space.
In the existing source code, the terminology 'overflow page' is clearly preferred to 'overflow bucket'. [rhaas pgsql]$ git grep 'overflow page' | wc -l 75 [rhaas pgsql]$ git grep 'overflow bucket' | wc -l 1 In our off-list conversations, I too have found it very confusing when you've made reference to an overflow bucket. A hash table has a fixed number of buckets, and depending on the type of hash table the storage for each bucket may be linked together into some kind of a chain; here, a chain of pages. The 'bucket' logically refers to all of the entries that have hash codes such that (hc % nbuckets) == bucketno, regardless of which pages contain them. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers