What is Index ? Explain its Types?
Answers were Sorted based on User's Feedback
Answer / sajjan singh
Indexes are data structures that help SQL Server to find
particular rows of data fastly.
In a database, an index allows the database program to find
data in a table without scanning the entire table.
An index in a database is a list of values in a table with
the storage locations of rows in the table that contain each
value.
Indexes can be created on either a single column or a
combination of columns in a table and are implemented in the
form of B-trees.
Clustered Index: "A clustered index is a special type of
index that reorders the way records in the table are
physically stored.
Therefore table can have only one clustered index. The leaf
nodes of a clustered index contain the data pages."
Non Clustered Index: "A nonclustered index is a special type
of index in which the logical order of the index does not
match the physical stored order of the rows on disk.
The leaf nodes of a nonclustered index does not consist of
the data pages. Instead, the leaf nodes contain index rows."
Is This Answer Correct ? | 3 Yes | 0 No |
Answer / dinesh rathod
Index is a one important concept in .Net. So you should know the basic idea about index in .Net.
Is This Answer Correct ? | 0 Yes | 1 No |
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