SQL Server/T-SQL/Subquery/Subqueries ALL

Subqueries and ALL operator

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11> 12> CREATE TABLE works_on (emp_no INTEGER NOT NULL, 13> project_no CHAR(4) NOT NULL, 14> job CHAR (15) NULL, 15> enter_date DATETIME NULL) 16> 17> insert into works_on values (1, "p1", "analyst", "1997.10.1") 18> insert into works_on values (1, "p3", "manager", "1999.1.1") 19> insert into works_on values (2, "p2", "clerk", "1998.2.15") 20> insert into works_on values (2, "p2", NULL, "1998.6.1") 21> insert into works_on values (3, "p2", NULL, "1997.12.15") 22> insert into works_on values (4, "p3", "analyst", "1998.10.15") 23> insert into works_on values (5, "p1", "manager", "1998.4.15") 24> insert into works_on values (6, "p1", NULL, "1998.8.1") 25> insert into works_on values (7, "p2", "clerk", "1999.2.1") 26> insert into works_on values (8, "p3", "clerk", "1997.11.15") 27> insert into works_on values (7, "p1", "clerk", "1998.1.4") 28> 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) 1> 2> -- 3> 4> SELECT job FROM works_on WHERE emp_no <= ALL 5> (SELECT emp_no FROM employee) 6> GO job

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analyst manager (2 rows affected) 1> drop table works_on 2> GO 1> 2>

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