what is Covering Index ?
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Answer / rajesh kumar
An index is used to quickly locate the data record from
which the required data is read. In other words, the index
is only used to locate data records in the table and not to
return data.
A covering index is a special case where the index itself
contains the required data field and can return the data.
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Answer / midhu
- Index covering means that "Data can be found only using indexes, without touching the tables"
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Answer / saikat mukherjee
The observed improvement is due to the fact that the
nonclustered index contained all of the required information
to resolve the query. No Key Lookups were required. An index
that contains all information required to resolve the query
is known as a "Covering Index"; it completely covers the query.
Is This Answer Correct ? | 1 Yes | 2 No |
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