What is an index?
- Indexes of SQL Server are similar to the indexes in books. They help SQL Server retrieve the data quicker. Indexes are of two types. Clustered indexes and non-clustered indexes. Rows in the table are stored in the order of the clustered index key.
- There can be only one clustered index per table.
- Non-clustered indexes have their own storage separate from the table data storage.
- Non-clustered indexes are stored as B-tree structures.
- Leaf level nodes having the index key and it's row locater
What is an index?
Indexes help us to find data faster. It can be created on a single column or a combination of columns. A table index helps to arrange the values of one or more columns in a specific order.
Syntax:CREATE [ UNIQUE ] [ CLUSTERED | NONCLUSTERED ] INDEX index_name ON table_name
