[ https://issues.apache.org/jira/browse/ORC-397?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Owen O'Malley moved HIVE-18608 to ORC-397: ------------------------------------------ Affects Version/s: (was: 2.2.1) (was: 2.4.0) (was: 3.0.0) Component/s: (was: ORC) Workflow: jira (was: no-reopen-closed, patch-avail) Key: ORC-397 (was: HIVE-18608) Project: ORC (was: Hive) > ORC should allow selectively disabling dictionary-encoding on specified > columns > ------------------------------------------------------------------------------- > > Key: ORC-397 > URL: https://issues.apache.org/jira/browse/ORC-397 > Project: ORC > Issue Type: New Feature > Reporter: Mithun Radhakrishnan > Assignee: Mithun Radhakrishnan > Priority: Major > Attachments: HIVE-18608.1-branch-2.2.patch, > HIVE-18608.2-branch-2.2.patch > > > Just as ORC allows the choice of columns to enable bloom-filters on, it would > be nice to have a way to specify which columns {{DICTIONARY_V2}} encoding > should be disabled on. > Currently, the choice of dictionary-encoding depends on the results of > sampling the first row-stride within a stripe. If the user knows that a > column's cardinality is bound to prevent an effective dictionary, she might > choose to simply disable it on just that column, and avoid the cost of > sampling in the first row-stride. -- This message was sent by Atlassian JIRA (v7.6.3#76005)