How can I query the database using shell and get the results?

To search the database and return results, you can use command line tools such as mysql or sqlite3 in the shell. Here is an example of querying a database using mysql:

1. Firstly, connect to the database using the following command:

mysql -u [username] -p [database_name]

In this, [username] is the database username and [database_name] is the name of the database to connect to. After executing this command, the system will prompt for the password.

1. After entering the password, it is possible to use SQL statements to query the database. For example, to retrieve all data from a table named users, you can execute the following command:

SELECT * FROM users;

1. The results of the query will be displayed in table form on the terminal. If you want to save the results to a file, you can use the redirection operator “>”, for example:

SELECT * FROM users > results.txt

This will save the query results to a file named results.txt.

1. After the query is completed, you can use the exit command to disconnect from the database.

exit

Similarly, if you are querying a database using sqlite3, you can use the following command:

sqlite3 [database_name]

After that, use SQL commands to query the database, and once the query is completed, exit the database using the .exit command.

The above is the method of querying the database and returning results in the shell, with specific details varying according to the database and tools being used.