[ https://issues.apache.org/jira/browse/PHOENIX-6154?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Chinmay Kulkarni reassigned PHOENIX-6154: ----------------------------------------- Assignee: (was: Chinmay Kulkarni) > Move the check for existence of child views and task addition to drop those > child views to the client side when dropping a table/view > ------------------------------------------------------------------------------------------------------------------------------------- > > Key: PHOENIX-6154 > URL: https://issues.apache.org/jira/browse/PHOENIX-6154 > Project: Phoenix > Issue Type: Sub-task > Affects Versions: 5.0.0, 4.15.0 > Reporter: Chinmay Kulkarni > Priority: Major > Fix For: 5.1.0, 4.16.0 > > > When we issue a {{DROP TABLE/VIEW}}, if the table/view being dropped has > child views (and {{CASCADE}} is provided), we add a > {{[DropChildViewsTask|https://github.com/apache/phoenix/blob/1d844950bb4ec8221873ecd2b094c20f427cd984/phoenix-core/src/main/java/org/apache/phoenix/coprocessor/tasks/DropChildViewsTask.java]}} > in the {{SYSTEM.TASK}} table (see > [this|https://github.com/apache/phoenix/blob/1d844950bb4ec8221873ecd2b094c20f427cd984/phoenix-core/src/main/java/org/apache/phoenix/coprocessor/MetaDataEndpointImpl.java#L2479]). > This means that *while holding the row lock* for the table/view’s header row > ([here|https://github.com/apache/phoenix/blob/1d844950bb4ec8221873ecd2b094c20f427cd984/phoenix-core/src/main/java/org/apache/phoenix/coprocessor/MetaDataEndpointImpl.java#L2253]) > we do the following: > # Make an > [RPC|https://github.com/apache/phoenix/blob/1d844950bb4ec8221873ecd2b094c20f427cd984/phoenix-core/src/main/java/org/apache/phoenix/coprocessor/MetaDataEndpointImpl.java#L2459-L2461] > to the region hosting {{SYSTEM.CHILD_LINK}} to scan it in order to find > child views. > # If any child views are found in the step above, we make additional RPCs to > the region hosting {{SYSTEM.TASK}} to > {{[UPSERT|https://github.com/apache/phoenix/blob/1d844950bb4ec8221873ecd2b094c20f427cd984/phoenix-core/src/main/java/org/apache/phoenix/coprocessor/MetaDataEndpointImpl.java#L2479-L2484]}} > a {{DropChildViewsTask}} for immediate child views. > # We [send remote > mutations|https://github.com/apache/phoenix/blob/1d844950bb4ec8221873ecd2b094c20f427cd984/phoenix-core/src/main/java/org/apache/phoenix/coprocessor/MetaDataEndpointImpl.java#L2298-L2302] > to drop parent→child links from the {{SYSTEM.CHILD_LINK}} table. > Of the above extra RPCs, note that even if the table/view has no child views > or if {{CASCADE}} is not provided, we will still do the first RPC from the > server while holding a row lock. > We should move this check to the client (issue a scan against > SYSTEM.CHILD_LINK to see if a single linking row exists) and also add the > task from the client. -- This message was sent by Atlassian Jira (v8.3.4#803005)