SQL Server/T-SQL/Table/Table Alias

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Aliasing the table helps the readability of your query

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary int ) 5> GO 1> 2> create table job( 3> ID int, 4> title nvarchar (10), 5> averageSalary int) 6> GO 1> 2> 3> insert into employee (ID, name, salary) values (1, "Jason", 1234) 4> GO (1 rows affected) 1> insert into employee (ID, name, salary) values (2, "Robert", 4321) 2> GO (1 rows affected) 1> insert into employee (ID, name, salary) values (3, "Celia", 5432) 2> GO (1 rows affected) 1> insert into employee (ID, name, salary) values (4, "Linda", 3456) 2> GO (1 rows affected) 1> insert into employee (ID, name, salary) values (5, "David", 7654) 2> GO (1 rows affected) 1> insert into employee (ID, name, salary) values (6, "James", 4567) 2> GO (1 rows affected) 1> insert into employee (ID, name, salary) values (7, "Alison", 8744) 2> GO (1 rows affected) 1> insert into employee (ID, name, salary) values (8, "Chris", 9875) 2> GO (1 rows affected) 1> insert into employee (ID, name, salary) values (9, "Mary", 2345) 2> GO (1 rows affected) 1> 2> insert into job(ID, title, averageSalary) values(1,"Developer",3000) 3> GO (1 rows affected) 1> insert into job(ID, title, averageSalary) values(2,"Tester", 4000) 2> GO (1 rows affected) 1> insert into job(ID, title, averageSalary) values(3,"Designer", 5000) 2> GO (1 rows affected) 1> insert into job(ID, title, averageSalary) values(4,"Programmer", 6000) 2> GO (1 rows affected) 1> 2> 3> select * from employee; 4> GO ID name salary


---------- -----------
         1 Jason             1234
         2 Robert            4321
         3 Celia             5432
         4 Linda             3456
         5 David             7654
         6 James             4567
         7 Alison            8744
         8 Chris             9875
         9 Mary              2345

(9 rows affected) 1> select * from job; 2> GO ID title averageSalary


---------- -------------
         1 Developer           3000
         2 Tester              4000
         3 Designer            5000
         4 Programmer          6000

(4 rows affected) 1> 2> 3> --Aliasing the table helps the readability of your query 5> 6> 7> SELECT p.*, s.title 8> FROM Employee p 9> INNER JOIN job s 10> ON p.ID = s.ID 11> 12> 13> 14> 15> drop table employee; 16> drop table job; 17> GO ID name salary title


---------- ----------- ----------
         1 Jason             1234 Developer
         2 Robert            4321 Tester
         3 Celia             5432 Designer
         4 Linda             3456 Programmer

(4 rows affected) 1>

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