Mostafa Mokhtar created HIVE-7982: ------------------------------------- Summary: Regression in explain with CBO enabled due to issuing query per K,V for the stats Key: HIVE-7982 URL: https://issues.apache.org/jira/browse/HIVE-7982 Project: Hive Issue Type: Bug Components: CBO Affects Versions: 0.14.0 Reporter: Mostafa Mokhtar Assignee: Mostafa Mokhtar Fix For: 0.14.0
With CBO we need the correct set of indexes to provide an efficient Read/Write access. These indexes improve performance of Explain plan and Analyzed table by 60% and 300%. {code} MySQL CREATE INDEX PART_COL_STATS_N50 ON PART_COL_STATS (DB_NAME,TABLE_NAME,COLUMN_NAME) USING BTREE; MsSQL CREATE INDEX PART_COL_STATS_N50 ON PART_COL_STATS (DB_NAME,TABLE_NAME,COLUMN_NAME); Oracle CREATE INDEX PART_COL_STATS_N50 ON PART_COL_STATS (DB_NAME,TABLE_NAME,COLUMN_NAME); Postgres CREATE INDEX "PART_COL_STATS_N50" ON "PART_COL_STATS" USING btree ("DB_NAME","TABLE_NAME","COLUMN_NAME"); {code} -- This message was sent by Atlassian JIRA (v6.3.4#6332)