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Aleksey Yeschenko commented on CASSANDRA-7391: ---------------------------------------------- [~jbellis] Should this be shifted to 3.1? > Partial indexes > --------------- > > Key: CASSANDRA-7391 > URL: https://issues.apache.org/jira/browse/CASSANDRA-7391 > Project: Cassandra > Issue Type: New Feature > Components: API, Core > Reporter: Jonathan Ellis > Priority: Minor > Fix For: 3.0 > > > Indexing extremely common values is not useful (e.g. where 90% of rows have a > null value) because it's actually more efficient to just to a seq scan, so > indexing is just wasted effort. > Rather than requiring users to take that hit if they want anything indexed at > all, we should allow specifying a WHERE clause to CREATE INDEX specifying > which rows to include in the index. Could include UDF but useful even > without it. > http://www.postgresql.org/docs/9.3/static/indexes-partial.html -- This message was sent by Atlassian JIRA (v6.3.4#6332)