believe it or not, wikipedia has an excellent description of bloomfilters http://en.wikipedia.org/wiki/Bloom_filter
On 4/16/13, Anupam Singh <[email protected]> wrote: > Many join implementations use bloom filters built on the smaller to > eliminate rows on the larger tables in SQL queries. Many industrial RDBMS > engines will show the use of bloom filters in SQL explain plans. > > > For instance, oracle explain plans call these joins bloom filters as > SYS_OP_BLOOM_FILTER :- > > > https://forums.oracle.com/forums/thread.jspa?threadID=2470938 > > > It could be useful for performance tuning. Hope this helps. > > > -Anupam > > — > Sent from Mailbox for iPhone > > On Fri, Mar 29, 2013 at 11:32 PM, Ted Dunning <[email protected]> > wrote: > >> This isn't a very Hadoop question. >> A Bloom filter is a very low level data structure that doesn't really any >> correlate in SQL. It allows you to find duplicates quickly and >> probabilistically. In return for a small probability of a false >> positive, >> it uses less memory. >> On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <[email protected]> wrote: >>> Can some one give a simple analogy of Bloom Filter in SQL. >>> I am trying to understand and always get confused. >>> Thanks >>> -- Ted.
