SQL Alias

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You can specify an alias for the table name or column name by using SQL.

SQL Alias

You can specify an alias for the table name or column name by using SQL.

Basically, create an alias in order to allow the column names more readable.

SQL syntax column aliases

SELECT column_name AS alias_name
FROM table_name;

SQL table alias syntax

SELECT column_name(s)
FROM table_name AS alias_name;

The demo database

In this tutorial, we will use w3big sample database.

The following is a selected "Websites" table data:

+----+--------------+---------------------------+-------+---------+
| id | name         | url                       | alexa | country |
+----+--------------+---------------------------+-------+---------+
| 1  | Google       | https://www.google.cm/    | 1     | USA     |
| 2  | 淘宝          | https://www.taobao.com/   | 13    | CN      |
| 3  | 本教程      | http://www.w3big.com/    | 4689  | CN      |
| 4  | 微博          | http://weibo.com/         | 20    | CN      |
| 5  | Facebook     | https://www.facebook.com/ | 3     | USA     |
| 7  | stackoverflow | http://stackoverflow.com/ |   0 | IND     |
+----+---------------+---------------------------+-------+---------+

Here is the data "access_log" website access record table:

mysql> SELECT * FROM access_log;
+-----+---------+-------+------------+
| aid | site_id | count | date       |
+-----+---------+-------+------------+
|   1 |       1 |    45 | 2016-05-10 |
|   2 |       3 |   100 | 2016-05-13 |
|   3 |       1 |   230 | 2016-05-14 |
|   4 |       2 |    10 | 2016-05-14 |
|   5 |       5 |   205 | 2016-05-14 |
|   6 |       4 |    13 | 2016-05-15 |
|   7 |       3 |   220 | 2016-05-15 |
|   8 |       5 |   545 | 2016-05-16 |
|   9 |       3 |   201 | 2016-05-17 |
+-----+---------+-------+------------+
9 rows in set (0.00 sec)

Examples of column aliases

The following SQL statement specifies two aliases, the alias name is a column, a column alias country. Tip: If the column name contains spaces, requires the use of double quotation marks or brackets:

Examples

SELECT name AS n, country AS c
FROM Websites;

Execution output:

In the following SQL statement, we have four columns (name, url, alexa and country) together and create an alias called "site_info" of:

Examples

SELECT name, CONCAT (url, ',', alexa, ',', country) AS site_info
FROM Websites;

Execution output:

Examples alias table

The following SQL statement to select the "Tutorial" in the access log. We use the "Websites" and "access_log" table, and they were designated table alias "w" and "a" (by using an alias to make SQL shorter):

Examples

SELECT w.name, w.url, a.count, a.date
FROM Websites AS w, access_log AS a
WHERE a.site_id = w.id and w.name = "tutorial";

Execution output:

The same SQL statement without aliases:

Examples

SELECT Websites.name, Websites.url, access_log.count, access_log.date
FROM Websites, access_log
WHERE Websites.id = access_log.site_id and Websites.name = "tutorial";

Execution output: