SQL Server/T-SQL/Table/Column Index

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Reference column index

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36> 37> CREATE TABLE works_on (emp_no INTEGER NOT NULL, 38> project_no CHAR(4) NOT NULL, 39> job CHAR (15) NULL, 40> enter_date DATETIME NULL) 41> 42> insert into works_on values (1, "p1", "analyst", "1997.10.1") 43> insert into works_on values (1, "p3", "manager", "1999.1.1") 44> insert into works_on values (2, "p2", "clerk", "1998.2.15") 45> insert into works_on values (2, "p2", NULL, "1998.6.1") 46> insert into works_on values (3, "p2", NULL, "1997.12.15") 47> insert into works_on values (4, "p3", "analyst", "1998.10.15") 48> insert into works_on values (5, "p1", "manager", "1998.4.15") 49> insert into works_on values (6, "p1", NULL, "1998.8.1") 50> insert into works_on values (7, "p2", "clerk", "1999.2.1") 51> insert into works_on values (8, "p3", "clerk", "1997.11.15") 52> insert into works_on values (7, "p1", "clerk", "1998.1.4") 53> 54> 55> SELECT project_no, COUNT(*) emp_quantity 56> FROM works_on 57> GROUP BY project_no 58> ORDER BY 2 DESC 59> 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) project_no emp_quantity

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p1 4 p2 4 p3 3 (3 rows affected) 1> 2> drop table works_on 3> GO 1> 

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