The follow tasks make up our recommended strategy for designing indexes: Experienced database administrators can design a good set of indexes, but this task is very complex, time-consuming, and error-prone even for moderately complex databases and workloads.
Understanding the characteristics of your database, queries, and data columns can help you design optimal indexes.
Wide indexes, on the other hand, cover more queries.
Data and index information can then be read in parallel by the multiple disk heads. This would guarantee that all disks are being accessed because all data and indexes are spread evenly across all disks, regardless of which way the data is accessed.
This is also a simpler approach for system administrators.
The selection of the right indexes for a database and its workload is a complex balancing act between query speed and update cost.
Narrow indexes, or indexes with few columns in the index key, require less disk space and maintenance overhead.
When you design an index, consider the following database guidelines: The term SARGable in relational databases refers to a Search ARGument-able predicate that can leverage an index to speed up the execution of the query.
When you design an index consider the following column guidelines: You can also customize the initial storage characteristics of the index to optimize its performance or maintenance by setting an option such as FILLFACTOR.
An index is an on-disk or in-memory structure associated with a table or view that speeds retrieval of rows from the table or view.
An index contains keys built from one or more columns in the table or view.
For on-disk indexes, these keys are stored in a structure (B-tree) that enables SQL Server to find the row or rows associated with the key values quickly and efficiently.