SQL Server/T-SQL Tutorial/Query/Query Hints
Using Query Hints
<source lang="sql">
4> 5> 6> CREATE TABLE employee( 7> id INTEGER NOT NULL PRIMARY KEY, 8> first_name VARCHAR(10), 9> last_name VARCHAR(10), 10> salary DECIMAL(10,2), 11> start_Date DATETIME, 12> region VARCHAR(10), 13> city VARCHAR(20), 14> managerid INTEGER 15> ); 16> GO 1> INSERT INTO employee VALUES (1, "Jason" , "Martin", 5890,"2005-03-22","North","Vancouver",3); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (2, "Alison", "Mathews",4789,"2003-07-21","South","Utown",4); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (3, "James" , "Smith", 6678,"2001-12-01","North","Paris",5); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (4, "Celia" , "Rice", 5567,"2006-03-03","South","London",6); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (5, "Robert", "Black", 4467,"2004-07-02","East","Newton",7); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (6, "Linda" , "Green" , 6456,"2002-05-19","East","Calgary",8); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (7, "David" , "Larry", 5345,"2008-03-18","West","New York",9); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (8, "James" , "Cat", 4234,"2007-07-17","West","Regina",9); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (9, "Joan" , "Act", 6123,"2001-04-16","North","Toronto",10); 2> GO (1 rows affected) 1> 2> select * from employee; 3> GO id first_name last_name salary start_Date region city managerid
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1 Jason Martin 5890.00 2005-03-22 00:00:00.000 North Vancouver 3 2 Alison Mathews 4789.00 2003-07-21 00:00:00.000 South Utown 4 3 James Smith 6678.00 2001-12-01 00:00:00.000 North Paris 5 4 Celia Rice 5567.00 2006-03-03 00:00:00.000 South London 6 5 Robert Black 4467.00 2004-07-02 00:00:00.000 East Newton 7 6 Linda Green 6456.00 2002-05-19 00:00:00.000 East Calgary 8 7 David Larry 5345.00 2008-03-18 00:00:00.000 West New York 9 8 James Cat 4234.00 2007-07-17 00:00:00.000 West Regina 9 9 Joan Act 6123.00 2001-04-16 00:00:00.000 North Toronto 10
(9 rows affected) 1> 2> 3> SELECT ID,salary 4> FROM employee 5> WHERE region = "North" 6> ORDER BY ID 7> OPTION (RECOMPILE) 8> 9> 10> 11> 12> drop table employee; 13> GO ID salary
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1 5890.00 3 6678.00 9 6123.00
(3 rows affected) 1> 2></source>
Using Table Hints (WITH (NOLOCK))
<source lang="sql">
5> 6> CREATE TABLE employee( 7> id INTEGER NOT NULL PRIMARY KEY, 8> first_name VARCHAR(10), 9> last_name VARCHAR(10), 10> salary DECIMAL(10,2), 11> start_Date DATETIME, 12> region VARCHAR(10), 13> city VARCHAR(20), 14> managerid INTEGER 15> ); 16> GO 1> INSERT INTO employee VALUES (1, "Jason" , "Martin", 5890,"2005-03-22","North","Vancouver",3); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (2, "Alison", "Mathews",4789,"2003-07-21","South","Utown",4); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (3, "James" , "Smith", 6678,"2001-12-01","North","Paris",5); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (4, "Celia" , "Rice", 5567,"2006-03-03","South","London",6); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (5, "Robert", "Black", 4467,"2004-07-02","East","Newton",7); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (6, "Linda" , "Green" , 6456,"2002-05-19","East","Calgary",8); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (7, "David" , "Larry", 5345,"2008-03-18","West","New York",9); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (8, "James" , "Cat", 4234,"2007-07-17","West","Regina",9); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (9, "Joan" , "Act", 6123,"2001-04-16","North","Toronto",10); 2> GO (1 rows affected) 1> 2> select * from employee; 3> GO id first_name last_name salary start_Date region city managerid
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1 Jason Martin 5890.00 2005-03-22 00:00:00.000 North Vancouver 3 2 Alison Mathews 4789.00 2003-07-21 00:00:00.000 South Utown 4 3 James Smith 6678.00 2001-12-01 00:00:00.000 North Paris 5 4 Celia Rice 5567.00 2006-03-03 00:00:00.000 South London 6 5 Robert Black 4467.00 2004-07-02 00:00:00.000 East Newton 7 6 Linda Green 6456.00 2002-05-19 00:00:00.000 East Calgary 8 7 David Larry 5345.00 2008-03-18 00:00:00.000 West New York 9 8 James Cat 4234.00 2007-07-17 00:00:00.000 West Regina 9 9 Joan Act 6123.00 2001-04-16 00:00:00.000 North Toronto 10
(9 rows affected) 1> 2> 3> 4> SELECT ID,first_name 5> FROM employee 6> WITH (NOLOCK) 7> WHERE id = 1 8> 9> 10> drop table employee; 11> GO ID first_name
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1 Jason
(1 rows affected) 1></source>