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https://issues.apache.org/jira/browse/IMPALA-12712?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17807859#comment-17807859
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Sai Hemanth Gantasala commented on IMPALA-12712:
------------------------------------------------
[~stigahuang] - I'm assigning this to me for now so that we don't lose track of
this issue.
> INVALIDATE METADATA <table> should set a better createEventId
> -------------------------------------------------------------
>
> Key: IMPALA-12712
> URL: https://issues.apache.org/jira/browse/IMPALA-12712
> Project: IMPALA
> Issue Type: Bug
> Components: Catalog
> Reporter: Quanlong Huang
> Assignee: Sai Hemanth Gantasala
> Priority: Major
>
> "INVALIDATE METADATA <table>" can be used to bring up a table in Impala's
> catalog cache if the table exists in HMS. For instance, when HMS event
> processing is disabled, we can use it in Impala to bring up tables that are
> created outside Impala.
> The createEventId for such tables are always set as -1:
> [https://github.com/apache/impala/blob/6ddd69c605d4c594e33fdd39a2ca888538b4b8d7/fe/src/main/java/org/apache/impala/catalog/CatalogServiceCatalog.java#L2243-L2246]
> This is problematic when event-processing is enabled. DropTable events and
> RenameTable events use the createEventId to decide whether to remove the
> table in catalog cache. -1 will lead to always removing the table. Though it
> might be added back shortly in follow-up CreateTable events, in the period
> between them the table is missing in Impala, causing test failures like
> IMPALA-12266.
> A simpler reproducing of the issue is creating a table in Hive and launching
> Impala with a long event polling interval to mimic the delay on events. Note
> that we start Impala cluster after creating the table so Impala don't need to
> process the CREATE_TABLE event.
> {noformat}
> hive> create table debug_tbl (i int);
> bin/start-impala-cluster.py --catalogd_args=--hms_event_polling_interval_s=60
> {noformat}
> Drop the table in Impala and recreate it in Hive, so it doesn't exist in the
> catalog cache but exist in HMS. Run "INVALIDATE METADATA <table>" in Impala
> to bring it up before the DROP_TABLE event come.
> {noformat}
> impala> drop table debug_tbl;
> hive> create table debug_tbl (i int, j int);
> impala> invalidate metadata debug_tbl;
> {noformat}
> The table will be dropped by the DROP_TABLE event and then added back by the
> CREATE_TABLE event. Shown in catalogd logs:
> {noformat}
> I0115 16:30:15.376713 3208 JniUtil.java:177]
> 02457b6d5f174d1f:3bdeee1400000000] Finished execDdl request: DROP_TABLE
> default.debug_tbl issued by quanlong. Time spent: 417ms
> I0115 16:30:23.390962 3208 CatalogServiceCatalog.java:2777]
> 1840bd101f78d611:22079a5a00000000] Invalidating table metadata:
> default.debug_tbl
> I0115 16:30:23.404150 3208 Table.java:234]
> 1840bd101f78d611:22079a5a00000000] createEventId_ for table:
> default.debug_tbl set to: -1
> I0115 16:30:23.405138 3208 JniUtil.java:177]
> 1840bd101f78d611:22079a5a00000000] Finished resetMetadata request: INVALIDATE
> TABLE default.debug_tbl issued by quanlong. Time spent: 17ms
> I0115 16:30:55.108006 32760 MetastoreEvents.java:637] EventId: 8668853
> EventType: DROP_TABLE Successfully removed table default.debug_tbl
> I0115 16:30:55.108459 32760 MetastoreEvents.java:637] EventId: 8668855
> EventType: CREATE_TABLE Successfully added table default.debug_tbl
> {noformat}
> CC [~VenuReddy], [~hemanth619]
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