SQL Alias

There are two types of aliases that are used most frequently in SQL command: which is column alias and table alias.

Why ALIAS? There is some reasons alias to be use when querying a SQL command.

- alias in a long query can make your query easier to read and understand
- alias table is use when using a same table in one query
- alias column is to identify the column naming when used together with aggregate functions, then the column can be understand easily

Syntax for Column Name Alias is :

SELECT [COLUMN NAME] AS COLUMN_ALIAS FROM [TABLE NAME]

Syntax for Table Name Alias is :

SELECT [COLUMN NAME] FROM [TABLE NAME] AS TABLE_ALIAS

Example will using this table : Table GameScores

PlayerName Department Scores
Jason IT 3000
Irene IT 1500
Jane Marketing 1000
David Marketing 2500
Paul HR 2000
James HR 2000


EXAMPLE for Column Name Alias :

let's say we want to refer to a simple example that just change the table name as DepartmentGameScores

SQL statement :

SELECT * FROM GameScores AS DepartmentGameScores

Result:

Table DepartmentGameScores

PlayerName Department Scores
Jason IT 3000
Irene IT 1500
Jane Marketing 1000
David Marketing 2500
Paul HR 2000
James HR 2000


EXAMPLE for Table Name Alias :

let's say we want to refer to a simple example which is return sum of the scores in the table. this example is taken from SQL SUM

SQL statement :

SELECT SUM(Scores) AS Total_score
FROM
GameScores

Result:

 

Total_score
12000

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