SQL Server/T-SQL/System/SHOWPLAN TEXT

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SET SHOWPLAN_TEXT ON

   <source lang="sql">

19> 20> CREATE TABLE works_on (emp_no INTEGER NOT NULL, 21> project_no CHAR(4) NOT NULL, 22> job CHAR (15) NULL, 23> enter_date DATETIME NULL) 24> 25> insert into works_on values (1, "p1", "analyst", "1997.10.1") 26> insert into works_on values (1, "p3", "manager", "1999.1.1") 27> insert into works_on values (2, "p2", "clerk", "1998.2.15") 28> insert into works_on values (2, "p2", NULL, "1998.6.1") 29> insert into works_on values (3, "p2", NULL, "1997.12.15") 30> insert into works_on values (4, "p3", "analyst", "1998.10.15") 31> insert into works_on values (5, "p1", "manager", "1998.4.15") 32> insert into works_on values (6, "p1", NULL, "1998.8.1") 33> insert into works_on values (7, "p2", "clerk", "1999.2.1") 34> insert into works_on values (8, "p3", "clerk", "1997.11.15") 35> insert into works_on values (7, "p1", "clerk", "1998.1.4") 36> 37> select * from works_on 38> GO Msg 2714, Level 16, State 6, Server sqle\SQLEXPRESS, Line 20 There is already an object named "works_on" in the database. 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 Msg 2714, Level 16, State 6, Server sqle\SQLEXPRESS, Line 1 There is already an object named "employee" in the database. 1> 2> --The FORCE ORDER hint forces the optimizer to join tables in the order in which 3> --they are specified in a query 4> 5> SET SHOWPLAN_TEXT ON 6> GO 1> select emp_lname, emp_fname 2> from works_on JOIN employee 3> ON employee.emp_no = works_on.emp_no 4> WHERE works_on.job = "Analyst" 5> option (force order) 6> GO StmtText



select emp_lname, emp_fname

             from works_on JOIN employee
             ON employee.emp_no = works_on.emp_no
             WHERE works_on.job = "Analyst"
             option (force order)

(1 rows affected) StmtText


 |--Hash Match(Inner Join, HASH:([master].[dbo].[works_on].[emp_no])=([master].[dbo].[employee].[emp_no]))
      |--Table Scan(OBJECT:([master].[dbo].[works_on]), WHERE:([master].[dbo].[works_on].[job]="Analyst"))
      |--Table Scan(OBJECT:([master].[dbo].[employee]))

(3 rows affected) 1> SET SHOWPLAN_TEXT OFF 2> GO 1> drop table employee 2> drop table works_on 3> GO 1> 2>

      </source>
   
  


SET SHOWPLAN_TEXT ON for an index

   <source lang="sql">

23> CREATE TABLE works_on (emp_no INTEGER NOT NULL, 24> project_no CHAR(4) NOT NULL, 25> job CHAR (15) NULL, 26> enter_date DATETIME NULL) 27> 28> insert into works_on values (1, "p1", "analyst", "1997.10.1") 29> insert into works_on values (1, "p3", "manager", "1999.1.1") 30> insert into works_on values (2, "p2", "clerk", "1998.2.15") 31> insert into works_on values (2, "p2", NULL, "1998.6.1") 32> insert into works_on values (3, "p2", NULL, "1997.12.15") 33> insert into works_on values (4, "p3", "analyst", "1998.10.15") 34> insert into works_on values (5, "p1", "manager", "1998.4.15") 35> insert into works_on values (6, "p1", NULL, "1998.8.1") 36> insert into works_on values (7, "p2", "clerk", "1999.2.1") 37> insert into works_on values (8, "p3", "clerk", "1997.11.15") 38> insert into works_on values (7, "p1", "clerk", "1998.1.4") 39> 40> select * from works_on 41> 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> 3> 4> SET SHOWPLAN_TEXT ON 5> GO 1> 2> select * from works_on WITH (index(0)) 3> where emp_no = 10102 4> GO StmtText


select * from works_on WITH (index(0))

      where emp_no = 10102

(1 rows affected) StmtText


 |--Table Scan(OBJECT:([master].[dbo].[works_on]), WHERE:([master].[dbo].[works_on].[emp_no]=(10102)))

(1 rows affected) 1> 2> SET SHOWPLAN_TEXT OFF 3> GO 1> drop table works_on 2> GO 1>

      </source>