What is the difference between Clustered and Non-clustered index?

1.	What is the difference between Clustered and Non-clustered index?
Answer» As EXPLAINED above, the differences can be BROKEN down into three small factors - Clustered index MODIFIES the way records are stored in a database based on the indexed column. A non-clustered index creates a separate entity within the table which references the ORIGINAL table. Clustered index is used for easy and speedy retrieval of data from the database, whereas, fetching records from the non-clustered index is relatively slower. In SQL, a table can have a single clustered index whereas it can have multiple non-clustered indexes.

Answer»

As EXPLAINED above, the differences can be BROKEN down into three small factors -

Clustered index MODIFIES the way records are stored in a database based on the indexed column. A non-clustered index creates a separate entity within the table which references the ORIGINAL table.
Clustered index is used for easy and speedy retrieval of data from the database, whereas, fetching records from the non-clustered index is relatively slower.
In SQL, a table can have a single clustered index whereas it can have multiple non-clustered indexes.

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