Hive Managed table vs external table

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 Managed Tables VS External Tables

Managed tables

A managed table is stored under the hive.metastore.warehouse.dir path property, by default in a folder path similar to /user/hive/warehouse/databasename.db/tablename/. The default location can be overridden by the location property during table creation. If a managed table or partition is dropped, the data and metadata associated with that table or partition are deleted. If the PURGE option is not specified, the data is moved to a trash folder for a defined duration.

Use managed tables when Hive should manage the lifecycle of the table, or when generating temporary tables.

External tables

An external table describes the metadata / schema on external files. External table files can be accessed and managed by processes outside of Hive. External tables can access data stored in sources such as Azure Storage Volumes (ASV) or remote HDFS locations. If the structure or partitioning of an external table is changed, an MSCK REPAIR TABLE table_name statement can be used to refresh metadata information.

Use external tables when files are already present or in remote locations, and the files should remain even if the table is dropped.

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