In my previous article SQL SERVER – Introduction to Force Index Query Hints – Index Hint I have discussed regarding how we can use Index Hints with any query. I just received email from one of my regular reader that are there any another methods for the same as it will be difficult to read the syntax of join.Yes, there is alternate way to do the same using OPTION clause however, as OPTION clause is specified at the end of the query we have to specify which table the index hint is put on.
Example 1: Using Inline Query Hint
USE AdventureWorks
GO
SELECT c.ContactID
FROM Person.Contact c
WITH (INDEX(AK_Contact_rowguid))
INNER JOIN Person.Contact pc
WITH (INDEX(PK_Contact_ContactID))
ON c.ContactID = pc.ContactID
GO
Example 2: Using OPTION clause
USE AdventureWorks
GO
SELECT c.ContactID
FROM Person.Contact c
INNER JOIN Person.Contact pc
ON c.ContactID = pc.ContactID
OPTION (TABLE HINT(c, INDEX (AK_Contact_rowguid)),
TABLE HINT(pc, INDEX (PK_Contact_ContactID)))
GO
Reference : Pinal Dave (http://blog.SQLAuthority.com)
Posted in Pinal Dave, SQL, SQL Authority, SQL Constraint and Keys, SQL Index, SQL Optimization, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology
