One way an “delete” can be implemented in Hawq is to use partition-exchange. It is ugly, but it provides away of implement more of a batch update/delete.
In order to do this, you need partitioned tables. For a delete, you select everything in the target partition out less the row(s) that you don’t want into a new partitioned table. The new table has the correct data in it. You use the alter table command to execute a partition exchange. You can us this general approach to perform an update. Generally, it is not a good design practice to use deletes with big data or in data warehouses. We don’t want to be trying to implement an OLTP system. However, if there is a business case to do this, it can be done in more of a batch fashion. — Jim Campbell [email protected] <mailto:[email protected]> O: 703-753-5970 M: 571-247-6511 On July 13, 2016 at 12:18:19 PM, Wales Wang ([email protected]) wrote: Actian vectorH can support update , delete on HDFS Wales Wang 在 2016-7-13，下午11:15，Vineet Goel <[email protected]> 写道： > Update and Delete is not supported yet, but it's in the future plan. There > is a JIRA on it I believe: > > https://issues.apache.org/jira/browse/HAWQ-304 > > Out of curiosity, what specific scenario are you trying to solve that > requires update/delete ? > > > -Vineet > > > > On Tue, Jul 12, 2016 at 7:10 PM, jinzhy <[email protected]> wrote: > >> hello everybody， >> >> Can HAWQ or Pivotal HD support 'delete' or 'update' operation in >> HDFS now？I can only create append only table in my computer。 >> >> >> >> >> >> >> >> >> >> --------------------------------------------------------------------------------------------------- >> >> Confidentiality Notice: The information contained in this e-mail and any >> accompanying attachment(s) >> is intended only for the use of the intended recipient and may be >> confidential and/or privileged of >> Neusoft Corporation, its subsidiaries and/or its affiliates. If any reader >> of this communication is >> not the intended recipient, unauthorized use, forwarding, printing, >> storing, disclosure or copying >> is strictly prohibited, and may be unlawful.If you have received this >> communication in error,please >> immediately notify the sender by return e-mail, and delete the original >> message and all copies from >> your system. Thank you. >> >> --------------------------------------------------------------------------------------------------- >> >>
