Analyze Poor Performing Queries For Optimization

  • Query Only When You Must

  • Select Only Columns You Need

  • Use Parameterized Queries As Much As Possible

  • Avoid correlated subqueries

  • Rewrite Subqueries to Use JOIN

  • Avoid Looping

  • Use CTE – Common Table Expression

  • If Possible Move Frequently Used Queries Into Views

  • Apply Indexes Effectively

    • Create Highly-Selective Indexes

    • Create Multiple-Column Indexes

    • Avoid Indexing Small Tables

    • Use Indexes with Filter Clauses

      • SARG operators  include =, >, <, >=, <=, IN, BETWEEN, and LIKE .

    • Index the ORDER-BY / GROUP-BY / DISTINCT Columns for Better Response Time

    • Use Execution Plan tool in SQL Server for creating indexes