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Todd Lipcon commented on HIVE-21487: ------------------------------------ Seems that this cluster is in some state where all compactions are failing (I think due to some other testing going on with a strange setup). The query is likely coming from CompactionTxnHandler.checkFailedCompactions. It's possible this isn't a hot enough code path to be worth a really large index, but perhaps it's worth one at least on ethe database/table level. > COMPLETED_COMPACTIONS table missing appropriate indexes > ------------------------------------------------------- > > Key: HIVE-21487 > URL: https://issues.apache.org/jira/browse/HIVE-21487 > Project: Hive > Issue Type: Bug > Affects Versions: 3.1.1 > Reporter: Todd Lipcon > Priority: Major > > Looking at a MySQL install where HMS is pointed on Hive 3.1, I see a constant > stream of queries of the form: > {code} > select CC_STATE from COMPLETED_COMPACTIONS where CC_DATABASE = > 'tpcds_orc_exact_1000' and CC_TABLE = 'catalog_returns' and CC_PARTITION = > 'cr_returned_date_sk=2452851' and CC_STATE != 'a' order by CC_ID desc; > {code} > but the COMPLETED_COMPACTIONS table has no index. In this case it's resulting > in a full table scan over 115k rows, which takes around 100ms. -- This message was sent by Atlassian JIRA (v7.6.3#76005)