[ https://issues.apache.org/jira/browse/IMPALA-10468?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Vihang Karajgaonkar updated IMPALA-10468: ----------------------------------------- Issue Type: Bug (was: Improvement) > DROP events which are generated while a batch is being processed may add > table incorrectly > ------------------------------------------------------------------------------------------ > > Key: IMPALA-10468 > URL: https://issues.apache.org/jira/browse/IMPALA-10468 > Project: IMPALA > Issue Type: Bug > Reporter: Vihang Karajgaonkar > Assignee: Vihang Karajgaonkar > Priority: Major > > One of the problems with CREATE/DROP events is that they may occur while a > batch is being processed and hence EventsProcessor may not able aware of that. > For example, consider the following sequence of statements: > create table foo (c1 int); > drop table foo; > create table foo (c2 int); > drop table foo; > These statements will generate CREATE_TABLE, DROP_TABLE, CREATE_TABLE, > DROP_TABLE event sequence. Generally, if all these 4 events are fetched in a > batch, then the first CREATE_TABLE and third CREATE_TABLE is ignored because > it is followed by the a DROP_TABLE in the sequence and the DROP_TABLE events > take no effect since the table doesn't exist in catalogd anymore. > However, if the events processor fetches these events in 2 batches (3 and 1) > then after the first batch of CREATE_TABLE, DROP_TABLE, CREATE_TABLE is > processed, the third event will add the table foo in the catalogd. The > subsequent batch's DROP_TABLE will be processed and remove the table, but > between the two batches, catalogd will say that a table called foo exists. > This can lead to statements getting errored out. Eg. a statement like create > table foo (c3 int) after the above statements will error out with a > TableAlreadyExists error. > The problem happens for databases too. So far I have not been able to > reproduce this for Partitions but I don't see why it will not happen with > Partitions also. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org For additional commands, e-mail: issues-all-h...@impala.apache.org