In this article we explore the role of Indexes in SQL Server performance
One of the most complicated features considered by many working on SQL Database is its indexes. Although, a bit confusing, SQL Indexes play a very important role in your overall performance and you can really work faster and efficiently with some great indexes. On the other hand, poorly managed indexes can make you feel helpless working on SQL database. In this article, you will learn some quick insights about SQL Server Indexes and how to work with them in a proper manner.
The Basic Steps for Managing indexes
First of all, remember that SQL Server Indexes are not as tough as you might think; you just follow a simple process. You first need to reduce all the overlapping indexes in your SQL Server, then eliminate all the useless indexes and then add the required missing indexes followed by tuning the resourceful query plans along with heaps of clustered indexes.
Difference between Clustered and Non Clustered SQL Indexes
Many times, people working on SQL server get confused between clustered and non clustered SQL indexes. Well, the difference between the two is that the former stores and sorts data rows in a particular table depending on key values, while the latter comprises of a key value along with a pointer for the data in a clustered index. In other words, the main difference between the two is that the clustered indexes helps controlling the data pages in physical order, while the non clustered indexes help managing even the different columns in the table of the server and it doesn’t impact on the storing or ordering of the data saved.
B-Tree Index Structure
While discussing the SQL Indexes, it is important to throw some light on the B-Tree Index Structure that are greatly impacted by the columns the user specify as key columns in the server; moreover, these B-Tree Structures have two levels; including the root level and the leaves level. Usually, the clustered indexes are considered as leaf level pages that comprise of the data in the SQL table; while the non clustered ones comprises of the key value and pointer as leaf level pages.
Limitations of Indexes
While there are more advantages of using the SQL indexes, we must also acquaint you with some limitations of the same for a better understanding of this great feature. Firstly, remember that you can only have one clustered index for one table. Secondly, no matter, whether it is a clustered or a non clustered index, you can add up to only 900 bytes or 16 columns in it. Lastly, up to 999 non clustered indexes for each table are easily supported by the SQL Server Database.
SQL Server crashes can be prove to be way too costly for small businesses
A number of small businesses use the free SQL Server Express edition. Many of them operate with little support and a SQL Server crash can compromise the valuable data stored in the database. To avoid data loss in the event of a SQL crash, small business should consider investing in a sql server recovery tool like DataNumen SQL Recovery. This advanced application can swing into action after a crash and recover all records including indexes, embedded objects etc with aplomb. More over the tool can also be used to recover records which got deleted by mistake.
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