SQL Server/T-SQL/Index/Create Index — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
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Текущая версия на 10:21, 26 мая 2010
Содержание
Create a composite index: the compound values in both columns must be unique
1> CREATE TABLE employee (emp_no INTEGER NOT NULL,
2> emp_fname CHAR(20) NOT NULL,
3> emp_lname CHAR(20) NOT NULL,
4> dept_no CHAR(4) NULL)
5>
6> insert into employee values(1, "Matthew", "Smith", "d3")
7> insert into employee values(2, "Ann", "Jones", "d3")
8> insert into employee values(3, "John", "Barrimore","d1")
9> insert into employee values(4, "James", "James", "d2")
10> insert into employee values(5, "Elsa", "Bertoni", "d2")
11> insert into employee values(6, "Elke", "Hansel", "d2")
12> insert into employee values(7, "Sybill", "Moser", "d1")
13>
14> select * from employee
15> GO
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
emp_no emp_fname emp_lname dept_no
----------- -------------------- -------------------- -------
1 Matthew Smith d3
2 Ann Jones d3
3 John Barrimore d1
4 James James d2
5 Elsa Bertoni d2
6 Elke Hansel d2
7 Sybill Moser d1
(7 rows affected)
1>
2> -- Create a composite index: the compound values in both columns must be unique
3>
4> CREATE UNIQUE INDEX i_empno_prno ON employee (emp_no, dept_no)
5> WITH FILLFACTOR=80
6> GO
1>
2> drop index i_empno_prno on employee
3> drop table employee
4> GO
Create an index for a table
1> create table employee(
2> ID int,
3> name nvarchar (10),
4> salary int,
5> start_date datetime,
6> city nvarchar (10),
7> region char (1))
8> GO
1>
2> insert into employee (ID, name, salary, start_date, city, region)
3> values (1, "Jason", 40420, "02/01/94", "New York", "W")
4> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (2, "Robert",14420, "01/02/95", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (4, "Linda", 40620, "11/04/97", "New York", "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (5, "David", 80026, "10/05/98", "Vancouver","W")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (6, "James", 70060, "09/06/99", "Toronto", "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (7, "Alison",90620, "08/07/00", "New York", "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W")
3> GO
(1 rows affected)
1>
2> select * from employee
3> GO
ID name salary start_date city region
----------- ---------- ----------- ----------------------- ---------- ------
1 Jason 40420 1994-02-01 00:00:00.000 New York W
2 Robert 14420 1995-01-02 00:00:00.000 Vancouver N
3 Celia 24020 1996-12-03 00:00:00.000 Toronto W
4 Linda 40620 1997-11-04 00:00:00.000 New York N
5 David 80026 1998-10-05 00:00:00.000 Vancouver W
6 James 70060 1999-09-06 00:00:00.000 Toronto N
7 Alison 90620 2000-08-07 00:00:00.000 New York W
8 Chris 26020 2001-07-08 00:00:00.000 Vancouver N
9 Mary 60020 2002-06-09 00:00:00.000 Toronto W
(9 rows affected)
1>
2> --Indexing a table
3>
4> CREATE UNIQUE CLUSTERED INDEX EmployeeIndex
5> ON Employee (Id)
6> GO
1>
2>
3> drop table employee
4> GO
1>
Create a nonclustered index
1> CREATE TABLE employee (emp_no INTEGER NOT NULL,
2> emp_fname CHAR(20) NOT NULL,
3> emp_lname CHAR(20) NOT NULL,
4> dept_no CHAR(4) NULL)
5>
6> insert into employee values(1, "Matthew", "Smith", "d3")
7> insert into employee values(2, "Ann", "Jones", "d3")
8> insert into employee values(3, "John", "Barrimore","d1")
9> insert into employee values(4, "James", "James", "d2")
10> insert into employee values(5, "Elsa", "Bertoni", "d2")
11> insert into employee values(6, "Elke", "Hansel", "d2")
12> insert into employee values(7, "Sybill", "Moser", "d1")
13>
14> select * from employee
15> GO
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
emp_no emp_fname emp_lname dept_no
----------- -------------------- -------------------- -------
1 Matthew Smith d3
2 Ann Jones d3
3 John Barrimore d1
4 James James d2
5 Elsa Bertoni d2
6 Elke Hansel d2
7 Sybill Moser d1
(7 rows affected)
1>
2> -- Create a nonclustered index.
3>
4> CREATE INDEX i_empno ON employee (emp_no)
5>
6> drop index i_empno on employee
7> drop table employee
8> GO
1>
2>
3>
Create index based on two columns
18>
19> CREATE TABLE works_on (emp_no INTEGER NOT NULL,
20> project_no CHAR(4) NOT NULL,
21> job CHAR (15) NULL,
22> enter_date DATETIME NULL)
23>
24> insert into works_on values (1, "p1", "analyst", "1997.10.1")
25> insert into works_on values (1, "p3", "manager", "1999.1.1")
26> insert into works_on values (2, "p2", "clerk", "1998.2.15")
27> insert into works_on values (2, "p2", NULL, "1998.6.1")
28> insert into works_on values (3, "p2", NULL, "1997.12.15")
29> insert into works_on values (4, "p3", "analyst", "1998.10.15")
30> insert into works_on values (5, "p1", "manager", "1998.4.15")
31> insert into works_on values (6, "p1", NULL, "1998.8.1")
32> insert into works_on values (7, "p2", "clerk", "1999.2.1")
33> insert into works_on values (8, "p3", "clerk", "1997.11.15")
34> insert into works_on values (7, "p1", "clerk", "1998.1.4")
35>
36> select * from works_on
37> GO
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
emp_no project_no job enter_date
----------- ---------- --------------- -----------------------
1 p1 analyst 1997-10-01 00:00:00.000
1 p3 manager 1999-01-01 00:00:00.000
2 p2 clerk 1998-02-15 00:00:00.000
2 p2 NULL 1998-06-01 00:00:00.000
3 p2 NULL 1997-12-15 00:00:00.000
4 p3 analyst 1998-10-15 00:00:00.000
5 p1 manager 1998-04-15 00:00:00.000
6 p1 NULL 1998-08-01 00:00:00.000
7 p2 clerk 1999-02-01 00:00:00.000
8 p3 clerk 1997-11-15 00:00:00.000
7 p1 clerk 1998-01-04 00:00:00.000
(11 rows affected)
1>
2>
3> -- AND Operator
4>
5> CREATE INDEX i_works ON works_on(emp_no, enter_date)
6> GO
1>
2> SELECT * FROM works_on WHERE emp_no = 8 AND enter_date="11.15.1997"
3> GO
emp_no project_no job enter_date
----------- ---------- --------------- -----------------------
8 p3 clerk 1997-11-15 00:00:00.000
(1 rows affected)
1>
2> drop table works_on
3> GO
1>
2>
Create index full syntax template
1>
2> create table employee(
3> ID int,
4> name nvarchar (10),
5> salary int,
6> start_date datetime,
7> city nvarchar (10),
8> region char (1))
9> GO
1>
2> insert into employee (ID, name, salary, start_date, city, region)
3> values (1, "Jason", 40420, "02/01/94", "New York", "W")
4> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (2, "Robert",14420, "01/02/95", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (4, "Linda", 40620, "11/04/97", "New York", "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (5, "David", 80026, "10/05/98", "Vancouver","W")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (6, "James", 70060, "09/06/99", "Toronto", "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (7, "Alison",90620, "08/07/00", "New York", "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name, salary, start_date, city, region)
2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W")
3> GO
(1 rows affected)
1>
2>
3> select * from employee
4> GO
ID name salary start_date city region
----------- ---------- ----------- ----------------------- ---------- ------
1 Jason 40420 1994-02-01 00:00:00.000 New York W
2 Robert 14420 1995-01-02 00:00:00.000 Vancouver N
3 Celia 24020 1996-12-03 00:00:00.000 Toronto W
4 Linda 40620 1997-11-04 00:00:00.000 New York N
5 David 80026 1998-10-05 00:00:00.000 Vancouver W
6 James 70060 1999-09-06 00:00:00.000 Toronto N
7 Alison 90620 2000-08-07 00:00:00.000 New York W
8 Chris 26020 2001-07-08 00:00:00.000 Vancouver N
9 Mary 60020 2002-06-09 00:00:00.000 Toronto W
(9 rows affected)
1>
2> -- Create index full syntax template
3> CREATE UNIQUE CLUSTERED INDEX IX_Employee
4> ON Employee
5> ([Id], [Name] DESC)
6> GO
1>
2> drop index IX_Employee on employee
3> GO
1>
2> drop table employee
3> GO
1>
Shows the use of the INDEX hint
14>
15> CREATE TABLE works_on (emp_no INTEGER NOT NULL,
16> project_no CHAR(4) NOT NULL,
17> job CHAR (15) NULL,
18> enter_date DATETIME NULL)
19>
20> insert into works_on values (1, "p1", "analyst", "1997.10.1")
21> insert into works_on values (1, "p3", "manager", "1999.1.1")
22> insert into works_on values (2, "p2", "clerk", "1998.2.15")
23> insert into works_on values (2, "p2", NULL, "1998.6.1")
24> insert into works_on values (3, "p2", NULL, "1997.12.15")
25> insert into works_on values (4, "p3", "analyst", "1998.10.15")
26> insert into works_on values (5, "p1", "manager", "1998.4.15")
27> insert into works_on values (6, "p1", NULL, "1998.8.1")
28> insert into works_on values (7, "p2", "clerk", "1999.2.1")
29> insert into works_on values (8, "p3", "clerk", "1997.11.15")
30> insert into works_on values (7, "p1", "clerk", "1998.1.4")
31>
32> select * from works_on
33> GO
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
emp_no project_no job enter_date
----------- ---------- --------------- -----------------------
1 p1 analyst 1997-10-01 00:00:00.000
1 p3 manager 1999-01-01 00:00:00.000
2 p2 clerk 1998-02-15 00:00:00.000
2 p2 NULL 1998-06-01 00:00:00.000
3 p2 NULL 1997-12-15 00:00:00.000
4 p3 analyst 1998-10-15 00:00:00.000
5 p1 manager 1998-04-15 00:00:00.000
6 p1 NULL 1998-08-01 00:00:00.000
7 p2 clerk 1999-02-01 00:00:00.000
8 p3 clerk 1997-11-15 00:00:00.000
7 p1 clerk 1998-01-04 00:00:00.000
(11 rows affected)
1>
2>
3> -- AND Operator
4>
5> CREATE INDEX i_works ON works_on(emp_no, enter_date)
6> GO
1>
2> -- Shows the use of the INDEX hint.
3> SET SHOWPLAN_TEXT ON
4> GO
1> select * from works_on WITH (INDEX(i_works))
2> where job = "Analyst"
3> and enter_date="12/01/1998"
4> GO
StmtText
---------------------------------------------------------------------------------------------------------------------
select * from works_on WITH (INDEX(i_works))
where job = "Analyst"
and enter_date="12/01/1998"
(1 rows affected)
StmtText
---------------------------------------------------------------------------------------------------------------------------------------------------
|--Filter(WHERE:([master].[dbo].[works_on].[job]="Analyst"))
|--Nested Loops(Inner Join, OUTER REFERENCES:([Bmk1000]))
|--Index Scan(OBJECT:([master].[dbo].[works_on].[i_works]), WHERE:([master].[dbo].[works_on].[enter_date]="1998-12-01 00:00:00.000"))
|--RID Lookup(OBJECT:([master].[dbo].[works_on]), SEEK:([Bmk1000]=[Bmk1000]) LOOKUP ORDERED FORWARD)
(4 rows affected)
1> SET SHOWPLAN_TEXT OFF
2> GO
1> drop table works_on
2> GO
1>