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Comment: link to StatsDev doc, add version information, misc. edits

Table of Contents

Introduction

This document describes changes to a) HiveQL, b) metastore schema, and c) metastore thrift API to support column level statistics in Hive. Please note that the document doesn’t describe the changes needed to persist histograms in the metastore yet.

For general information about Hive statistics, see Statistics in Hive.

Info
titleVersion information

Column statistics are introduced in Hive 0.10.0 by HIVE-1362.

HiveQL changes

HiveQL currently supports analyze command to compute statistics on tables and partitions. HiveQL’s analyze command will be extended to trigger statistics computation on one or more column in a Hive table/partition. The necessary changes to HiveQL are as below,

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