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Showing content from https://docs.databricks.com/aws/en/sql/language-manual/sql-ref-syntax-aux-cache-cache-table below:

CACHE TABLE | Databricks Documentation

Applies to: Databricks Runtime

Caches contents of a table or output of a query with the given storage level in Apache Spark cache. If a query is cached, then a temp view is created for this query. This reduces scanning of the original files in future queries.

CACHE [ LAZY ] TABLE table_name
  [ OPTIONS ( 'storageLevel' [ = ] value ) ] [ [ AS ] query ]

See Disk cache vs. Spark cache for the differences between disk caching and the Apache Spark cache.

• LAZY

  Only cache the table when it is first used, instead of immediately.

• table_name

  Identifies the Delta table or view to cache. The name must not include a temporal specification or options specification. If the table cannot be found Databricks raises a TABLE_OR_VIEW_NOT_FOUND error.

• OPTIONS ( 'storageLevel' [ = ] value )

  OPTIONS clause with storageLevel key and value pair. A warning is issued when a key other than storageLevel is used. The valid options for storageLevel are:

  • NONE
    • DISK_ONLY
    • DISK_ONLY_2
    • MEMORY_ONLY
    • MEMORY_ONLY_2
    • MEMORY_ONLY_SER
    • MEMORY_ONLY_SER_2
    • MEMORY_AND_DISK
    • MEMORY_AND_DISK_2
    • MEMORY_AND_DISK_SER
    • MEMORY_AND_DISK_SER_2
    • OFF_HEAP

  An Exception is thrown when an invalid value is set for storageLevel. If storageLevel is not explicitly set using OPTIONS clause, the default storageLevel is set to MEMORY_AND_DISK.

• query

  A query that produces the rows to be cached. It can be in one of following formats:

  • A SELECT statement
  • A TABLE statement
  • A FROM statement

SQL

> CACHE TABLE testCache OPTIONS ('storageLevel' 'DISK_ONLY') SELECT * FROM testData;

• CLEAR CACHE
• UNCACHE TABLE
• REFRESH TABLE
• REFRESH CACHE
• REFRESH FUNCTION

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