Skip inaccessible fragments

One benefit that fragmentation provides is the ability to skip table fragments that are unavailable during an I/O operation. For example, a query can proceed even when a fragment is located on a chunk that is currently down as a result of a disk failure. When this situation occurs, a disk failure affects only a portion of the data in the fragmented table. By contrast, tables that are not fragmented can become completely inaccessible if they are located on a disk that fails.

This function is controlled as follows:
  • By the database server administrator with the DATASKIP configuration parameter
  • By individual applications with the SET DATASKIP statement

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