In this article, I will use the following SQL Server environment. In this article, we will explore the query hint OPTION (FAST ‘N’) to improve the performance of a query for retrieving the specific number of rows quickly along with its impact. Some examples are Recompile, MAXDOP, OPTIMIZE FOR UNKNOWN. It instructs query optimizer to apply the hint throughout the SQL query execution. This hint is used to inform the optimizer to execute a query execution plan in the order the tables are specified in the query. One of the popular table hints is WITH(NOLOCK) to avoid default transaction isolation level and avoid locking issues in Select statements. Oracle provides users with the ability to influence how the query optimizer behaves and the decisions made to generate query run plans. Use index hints and optimizer hints as comments. Hints give us the opportunity, in cases where we have superior knowledge about the database, to. An optimizer hint is a code snippet within an SQL statement controlling the decisions of the optimizer. Suppose you want to use a specific index for your query to avoid a table scan, we can use table hints. Two star feature compatibility N/A N/A Very limited set of hints in MySQL. The optimizer is the hero of our story let me introduce the potential villains, Optimizer Hints. We have the following query hints in SQL Server. To use a specific operator, SQL Server might need to change other operators as well. SQL Server provides query hints in which you can force query optimizer to use a particular operator in the execution plan. In case you are new to Execution Plans in SQL Server, you can refer to this article, SQL Server Execution Plans overview to understand about them. In most of the cases, it is an effective plan, and it does not require any intervention for a query performance if all other things like statistics, indexes are in proper form. Once the user submits any query to SQL Server, it creates an optimized and cost-effective execution plan depending upon the statistics, indexes, and data distribution. In this article, we will introduce SQL queries hint and will analyze the OPTION(Fast ‘N’) hint in detail.
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