pengcheng xiong created HIVE-7654: ------------------------------------- Summary: A method to extrapolate columnStats for partitions of a table Key: HIVE-7654 URL: https://issues.apache.org/jira/browse/HIVE-7654 Project: Hive Issue Type: New Feature Reporter: pengcheng xiong Assignee: pengcheng xiong Priority: Minor Attachments: Extrapolate the Column Status.docx
In a PARTITIONED table, there are many partitions. For example, create table if not exists loc_orc ( state string, locid int, zip bigint ) partitioned by(year string) stored as orc; We assume there are 4 partitions, partition(year='2000'), partition(year='2001'), partition(year='2002') and partition(year='2003'). We can use the following command to compute statistics for columns state,locid of partition(year='2001') analyze table loc_orc partition(year='2001') compute statistics for columns state,locid; We need to know the “aggregated” column status for the whole table loc_orc. However, we may not have the column status for some partitions, e.g., partition(year='2002') and also we may not have the column status for some columns, e.g., zip bigint for partition(year='2001') We propose a method to extrapolate the missing column status for the partitions. -- This message was sent by Atlassian JIRA (v6.2#6252)