How indexing works in sql
Clustered and Nonclustered Indexes Described. 02/11/2019; 4 minutes to read +10; In this article. APPLIES TO: SQL Server Azure SQL Database Azure Synapse Analytics (SQL DW) Parallel Data Warehouse An index is an on-disk structure associated with a table or view that speeds retrieval of rows from the table or view. Indexes. They're one of the most powerful and misunderstood aspects of SQL performance. In this post we'll look at the purpose of an index, how to create and choose choose your index type. Then finish with a discussion of how to decide what to index and how to see if it's useful. Indexing is a critical part of database optimization. Indexing can dramatically increase query speed. See how indexes work and learn to build indexes with SQL.