Do make indexes containing another index make sense?

Posted by Orlando Dilasso on Stack Overflow See other posts from Stack Overflow or by Orlando Dilasso
Published on 2010-04-21T12:41:04Z Indexed on 2010/04/21 12:43 UTC
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sql-server

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index

Given a table (id, col1, col2), does it make sense to create the following indexes:

Index1 (col1) not unique

Index2 (col1, col2) not unique

I am faced with a legacy database that is full of those.

Can I safely delete Index1? Anwser needed for SQL Server and Oracle.

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