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Order of index columns [message #18908]

Wed, 20 February 2002 19:18

Jens Vogelgesang
Messages: 23
Registered: January 2002

Junior Member

I've a table containig several columns. Primary key consists out of to numbers.
(1,1)(1,2),(1,3),(1,4),(2,4),(2,5),(2,6)
Question: Whicj index will work faster?
field_1, field 2
or
field_2, field_1

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Re: Order of index columns [message #18912 is a reply to message #18908]

Thu, 21 February 2002 00:15

pratap kumar tripathy
Messages: 660
Registered: January 2002

Senior Member

both are same , but index will be picked depending on the order of the condition specified in where clause

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Re: Order of index columns [message #18942 is a reply to message #18912]

Thu, 21 February 2002 22:19

Jens Vogelgesang
Messages: 23
Registered: January 2002

Junior Member

The fist column has only a few different values
where the second has millions of different values.

Is it faster to access by column_1, columns 2
or
column 2, column 1.

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