INDEX in MySql

Discussion in 'MySQL' started by deriklogov, Jul 6, 2009.

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  1. #1
    Hey, today I found that my created indexed only has Cardinality:144
    and total database contains 800,000 records, my some of the indexes cover all records and this index covers only 144 ?
     
    deriklogov, Jul 6, 2009 IP
  2. jestep

    jestep Prominent Member

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    #2
    The cardinality will equal the number of unique rows. Of your 800K records, there are only 144 unique values in that column.
     
    jestep, Jul 6, 2009 IP