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Ashutosh Chauhan commented on HIVE-4271: ---------------------------------------- Left some comments on phabricator. > Limit precision of decimal type > ------------------------------- > > Key: HIVE-4271 > URL: https://issues.apache.org/jira/browse/HIVE-4271 > Project: Hive > Issue Type: Bug > Reporter: Gunther Hagleitner > Assignee: Gunther Hagleitner > Attachments: HIVE-4271.1.patch > > > The current decimal implementation does not limit the precision of the > numbers. This has a number of drawbacks. A maximum precision would allow us > to: > - Have SerDes/filformats store decimals more efficiently > - Speed up processing by implementing operations w/o generating java > BigDecimals > - Simplify extending the datatype to allow for decimal(p) and decimal(p,s) > - Write a more efficient BinarySortable SerDe for sorting/grouping/joining > Exact numeric datatype are typically used to represent money, so if the limit > is high enough it doesn't really become an issue. > A typical representation would pack 9 decimal digits in 4 bytes. So, with 2 > longs we can represent 36 digits - which is what I propose as the limit. > Final thought: It's easier to restrict this now and have the option to do the > things above than to try to do so once people start using the datatype. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira