Description

In this series, we will dive deeply in the SQL Server Indexing field, starting from the surface by understanding the internal structure of the SQL Server tables and indexes, going deeper by describing the guidelines and best practices that we can follow to design the most efficient index and what operations can be performed on the created indexes. Having these knowledges about the SQL Server indexes, we have all the tools that help us in testing the lower part of the ocean and dive deeper with the two main types of the SQL Server Indexes; the Clustered and Non-Clustered, and the other types of indexes that can be customized to serve us improving your environment. After that, the adventure becomes more interesting when learning how to use this knowledge to tune the performance of our queries and touch the bottom of the ocean. In our way back to the surface, and before celebrating our achievements, we will collect statistical information about these indexes and use this information to maintain the indexes to take benefits from it continuously and gain the best application performance.

In the previous articles of this series (see the full article TOC at bottom), we discussed the internal structure of both the SQL Server tables and indexes, the best practices that you can follow in order to design a proper index, list of operations that you can perform on the SQL Server indexes, how to design effective Clustered and Non-clustered indexes, the different types of SQL Server indexes, above and beyond Clustered and Non-clustered indexes classification and finally how to tune the performance of the bad queries using the different types of SQL Server Indexes. In this article, we will discuss how to gather statistical information about the index structure and the index usage information.

In the previous articles of this series (see the full article TOC at bottom), we discussed the internal structure of both SQL Server tables and indexes, the main guidelines that you can follow to design a proper index, the list of operations that can be performed on the SQL Server indexes, and finally how to design effective Clustered and Non-clustered indexes that the SQL Server Query Optimizer will always take benefits from, in speeding up the data retrieval process, which is the main goal of creating an index. In this article, we will go through the different types of SQL Server indexes, above and beyond Clustered and Non-clustered indexes classification, and when to use them.

In the previous articles of this series (see below for the full index of articles), we went through the internal structure of SQL Server tables and indexes, listed a number of guidelines that help in designing a proper index, discussed the operations that can be performed on SQL Server indexes and finally showed how to design and create a SQL Server Clustered index to speed up data retrieval operations. In this article, we will see how to design an effective Non-clustered index that will improve the performance of frequently used queries that are not covered with a Clustered index and, in doing so, enhance the overall system performance.

In the previous articles of this series (see bottom for a full index), we described, in detail, the structure of SQL Server tables and indexes, the basics and guidelines that help us in designing a proper index and finally the list of operations that can be performed on the SQL Server indexes. In this article, we will see how we could design an effective clustered index that the SQL Server Query Optimizer will always take benefits from, in speeding up the data retrieval process, which is the main goal of building an index.

In the previous articles of this series, we described the structure of the SQL Server tables and indexes, the main concepts that are used to describe the index and the basics and guidelines that are used to design the proper index. In this article, we will go through the operations that can be performed on the SQL Server indexes.

Creating Indexes

Before creating an index, it is better to follow the index design guidelines and best practices that are described in the previous article, to determine the columns that will participate in the index, the type of the created index, the suitable index options, such as the FillFactor or Sort in TempDB, and the storage location of that index.

In the previous article of this series, SQL Server Index Structure and Concepts, we described, in detail, the anatomy of QL Server indexes, the B-Tree structure, the properties of the indexes, the main types of indexes and the advantages of using the indexes for performance tuning.

In my previous article, SQL Server Table Structure Overview, we described, in detail, the difference between Heap table structure, in which the data pages are not sorted in any ordering criteria and the pages itself are not sorted or linked between each other, and Clustered tables, in which the data is sorted within the data pages and the pages will be also linked in a double linked list, based on the index key. In this article, we will go through the structure of the SQL Server index, itself.

Microsoft SQL Server is a relational database management systems (RDBMS) that, at its fundamental level, stores the data in tables. The tables are the database objects that behave as containers for the data, in which the data will be logically organized in rows and columns format. Each row is considered as an entity that is described by the columns that hold the attributes of the entity. For example, the customers table contains one row for each customer, and each customer is described by the table columns that hold the customer information, such as the CustomerName and CustomerAddress. The table rows have no predefined order, so that, to display the data in a specific order, you would need to specify the order that the rows will be returned in. Tables can be also used as a security boundary/mechanism, where database users can be granted permissions at the table level.