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Where can I use option recompile?
OPTION(RECOMPILE) tells the server not to cache the pan for given query. This means that another execution of the same query will require to elaborate a new(maybe different) plan. This is used in the queries with parameters to prevent parameter sniffing issue.
What is recompile stored procedure?
When SQL Server recompiles stored procedures, only the statement that caused the recompilation is compiled, instead of the complete procedure. If certain queries in a procedure regularly use atypical or temporary values, procedure performance can be improved by using the RECOMPILE query hint inside those queries.
What is recompile SQL?
sp_recompile looks for an object in the current database only. The queries used by stored procedures, or triggers, and user-defined functions are optimized only when they are compiled. SQL Server automatically recompiles stored procedures, triggers, and user-defined functions when it is advantageous to do this.
How SQL query is compiled?
The query processor goes through three phases before producing a plan from a query that you submit. First, it parses and normalizes the statements. Then it compiles the Transact SQL (T-SQL) code. Finally, it optimizes the SQL statement.
What is the use of with recompile statement?
Using WITH RECOMPILE effectively returns us to SQL Server 2000 behaviour, where the entire stored procedure is recompiled on every execution. A better alternative, on SQL Server 2005 and later, is to use the OPTION (RECOMPILE) query hint on just the statement that suffers from the parameter-sniffing problem.
Which command do you use to recompile a procedure?
Alter Procedure is used to recompile a procedure. The ALTER PROCEDURE statement is very similar to the ALTER FUNCTION statement.
What are query hints?
Query hints specify that the indicated hints are used in the scope of a query. They affect all operators in the statement. If UNION is involved in the main query, only the last query involving a UNION operation can have the OPTION clause. Query hints are specified as part of the OPTION clause.
What does option ( recompile ) do in SQL Server?
OPTION (RECOMPILE) is a statement level command that instructs query processor to pause batch execution, discard any stored query plans for the query, build a new plan, only now using the run-time values (parameters, local variables..), perform “constant folding” with passed in parameters.
When to use option ( recompile and Fast N )?
This means that another execution of the same query will require to elaborate a new (maybe different) plan. This is used in the queries with parameters to prevent parameter sniffing issue. This means that your query should have different plans depending on the parameter provided.
What is the difference between recompile and optimize for unknown?
OPTIMIZE FOR UNKNOWN doesn’t affect this feature of the engine. RECOMPILE suppresses this feature and tells the engine to discard the plan and not put it into the cache. Using (or not) actual parameter values during plan generation. Usually optimizer “sniffs” the parameter values and uses these values when generating the plan.
How to enable recompile in SQL Server management studio?
First, let us create a stored procedure that contains the keyword OPTION (RECOMPILE). Now enable the execution plan for your query window in SQL Server Management Studio (SSMS).