SQL SELECT statement

The SELECT statement is used to select data from the database.

SQL SELECT statement

The SELECT statement is used to select data from the database.
The result is stored in a result table, called the result set.

SQL SELECT syntax

SELECT column_name , column_name
FROM table_name ;
versus
SELECT * FROM table_name ;



Demo database

In this tutorial, we will use the RUNOOB sample database.
The following is the data selected from the “Websites” table:
 + ---- + -------------- + --------------------------- + - ------ + --------- +
| Id | name | url | alexa | country |
+ ---- + -------------- + --------------------------- + - ------ + --------- +
| 1 | Google | https://www.google.cm/ | 1 | USA |
| 2 | Taobao | https://www.taobao.com/ | 13 | CN |
| 3 | rookie tutorial | http://www.runoob.com/ | 4689 | CN |
| 4 | microblogging | http://weibo.com/ | 20 | CN |
5 | Facebook | https://www.facebook.com/ | 3 | USA |
+ ---- + -------------- + --------------------------- + - ------ + --------- +

SELECT Column instance

The following SQL statement selects the “name” and “country” columns from the “Websites” table:

Examples

SELECT Name , country FROM Websites ;
The output is:

SELECT * instance

The following SQL statement selects all columns from the “Websites” table:

Examples

SELECT * FROM Websites ;
The output is:

Results of the centralized navigation

Most database software systems allow the use of programming functions to navigate in the result set, such as: Move-To-First-Record, Get-Record-Content, Move-To-Next-Record, and so on.

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