The merits of VSAM alternate index

The alternate index is used to access records other than base key.

The dataset over which alternate index defined is called base cluster.

The merits.

  • Can be defined for both KSDS and ESDS
  • reduce data redundancy
  • Can have duplicates
  • Easy to define using IDCAMS
  • allow datasets to be accessed by both sequentially and randomly
VSAM alternate index merits
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The demerits

  • Performance degradation
  • Complex update logic

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Author: Srini

Experienced software developer. Skills in Development, Coding, Testing and Debugging. Good Data analytic skills (Data Warehousing and BI). Also skills in Mainframe.