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Harish Butani commented on HIVE-6439: ------------------------------------- yes agreed, let's add this post hive 0.13 branching. > Introduce CBO step in Semantic Analyzer > --------------------------------------- > > Key: HIVE-6439 > URL: https://issues.apache.org/jira/browse/HIVE-6439 > Project: Hive > Issue Type: Sub-task > Reporter: Harish Butani > Assignee: Harish Butani > Attachments: HIVE-6439.1.patch, HIVE-6439.2.patch, HIVE-6439.4.patch, > HIVE-6439.5.patch > > > This patch introduces CBO step in SemanticAnalyzer. For now the > CostBasedOptimizer is an empty shell. > The contract between SemAly and CBO is: > - CBO step is controlled by the 'hive.enable.cbo.flag'. > - When true Hive SemAly will hand CBO a Hive Operator tree (with operators > annotated with stats). If it can CBO will return a better plan in Hive AST > form. -- This message was sent by Atlassian JIRA (v6.1.5#6160)