Hands-On GUI Programming with C++ and Qt5
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SELECT

Most of the SQL statements are one-word short and self-explanatory. This statement, for example, is used to select one or more columns from a specific table and to obtain the data from the said columns. Let's check out some of the sample commands that use the SELECT statement.

The following command retrieves all the data of all the columns from the user table:

SELECT * FROM user;

The following command retrieves only the username column from the user table:

SELECT username FROM user;

The following command retrieves the username and password columns from the user table with the condition that the id equals 1:

SELECT username, password FROM user WHERE id = 1;

You can try out these commands by yourself using phpMyAdmin. To do that, click the SQL button located at the top of the menu in phpMyAdmin. After that, you can type the command in the text field below and click Go to execute the query:

To learn more about the SELECT statement, please refer to the following link: 
https://dev.mysql.com/doc/refman/5.7/en/select.html