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Oh ! Tunning..

hi,

what are main 3 purposes to rebuild an index?

advance thanks

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  • up

    Jammie Melia

    hi

    Thanks very much.

    Can u give me your gmail id, so that we can share more ?

    advance thanks

  • up

    Dane Sircy

    HI ALL,

    The purpose to rebuild an index is:

    a) When large datasets are added and removed, the need to rebuild indexes is common.
    b) In system that never update or delete rows, index rebuilding rarely improve performance
    c) In systems that do batch DML jobs, index rebuilding often improves SQL performance.

  • up

    Odis Stearn

    we rebuild an index if the
    INDEX height >3 and
    deleted leaf rows are greater than >20%
    we see this from
    sql> select height,if_rows,del_if_rows from index_stats;