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Benjamin Lerer commented on CASSANDRA-4476: ------------------------------------------- Here are my feedbacks: * Be carefull with whitespaces and indentation I had to use --ignore-space-change and --ignore-whitespace to be able to apply your patch. I had 82 lines with whitespace errors. * {{SecondaryIndex.supportOperator}} is overloaded. Secondary indices also support {{contains}} and {{contains key}} operators. You ignored them completely and broke that part of the code as you will see if you run {{ContainsRelationTest}}. * The goal of {{SecondaryIndexSearcher.highestSelectivityPredicate}} is to determine which index will be selecting the smallest amount of rows (highest selectivity). There is no reason why an equal operator should select less row than a slice operator. * Index expressions should be grouped when multiple slices apply to the same column. If a user does the following query Select * from myTable where a > 1 and a < 3 you should only scan from 1 to 3 and not from 1 to infinity or from -infinity to 3. * I have some trouble to understand the changes that you made in {{CompositesSearcher}}. Could you add some comments to explain your approach? * You should use meaningfull name for the test methods. Naming them {{bug4476}} force the reader to go to JIRA to have some clue about what the method is actualy testing. * Using {{pageSize}} as an instance variable in {{CQLTest}} is dangerous as it can have some unwanted effect on the other test methods (specially as JUnit does not guarantee the method execution order since Java 7). > Support 2ndary index queries with only inequality clauses (LT, LTE, GT, GTE) > ---------------------------------------------------------------------------- > > Key: CASSANDRA-4476 > URL: https://issues.apache.org/jira/browse/CASSANDRA-4476 > Project: Cassandra > Issue Type: Improvement > Components: API, Core > Reporter: Sylvain Lebresne > Assignee: Oded Peer > Priority: Minor > Labels: cql > Fix For: 3.0 > > Attachments: 4476-2.patch, cassandra-trunk-4476.patch > > > Currently, a query that uses 2ndary indexes must have at least one EQ clause > (on an indexed column). Given that indexed CFs are local (and use > LocalPartitioner that order the row by the type of the indexed column), we > should extend 2ndary indexes to allow querying indexed columns even when no > EQ clause is provided. > As far as I can tell, the main problem to solve for this is to update > KeysSearcher.highestSelectivityPredicate(). I.e. how do we estimate the > selectivity of non-EQ clauses? I note however that if we can do that estimate > reasonably accurately, this might provide better performance even for index > queries that both EQ and non-EQ clauses, because some non-EQ clauses may have > a much better selectivity than EQ ones (say you index both the user country > and birth date, for SELECT * FROM users WHERE country = 'US' AND birthdate > > 'Jan 2009' AND birtdate < 'July 2009', you'd better use the birthdate index > first). -- This message was sent by Atlassian JIRA (v6.3.4#6332)