After invalidating

Required after a table is created through the Hive shell, before the table is available for Impala queries.

after the table is created in Hive, allowing you to make individual tables visible to Impala without doing a full reload of the catalog metadata.

Impala 1.2.4 also includes other changes to make the metadata broadcast mechanism faster and more responsive, especially during Impala startup. In Impala 1.2 and higher, a dedicated daemon ( statement on another Impala node before accessing the new database or table from the other node.

Under certain circumstances performance gains can be made by transferring cache management from the authoring environment to a publishing instance.

It will then be the publishing environment (not the AEM authoring environment) that sends a cache invalidation request to Dispatcher when a published page is received.

The HTTP request causes Dispatcher to delete specific files from the cache.

Optionally, the Dispatcher then refreshes the cache with a new copy.

Because this operation adds a delay to the next query against each table, potentially expensive for large tables with many partitions, try to avoid using this option for day-to-day operations in a production environment.

HDFS permissions: The user ID that the user, must have execute permissions for all the relevant directories holding table data.

Issue an HTTP request that causes Dispatcher to delete cached files, and immediately retrieve and recache the file.

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