The MariaDB password on Linux is typically stored in the MariaDB configuration file, which is usually located at /etc/mysql/mariadb.conf.d/50-server.cnf or /etc/mysql/my.cnf. Within this configuration file, you will find a section called [client], where the password is stored under the parameter "password". However, it is important to note that the actual password is encrypted and not visible in plain text.
How to enable slow query logging in MariaDB on Linux?
To enable slow query logging in MariaDB on Linux, you can follow these steps:
- Open the MariaDB configuration file, usually located at /etc/my.cnf or /etc/mysql/my.cnf, using a text editor such as nano or vi.
- Locate the [mysqld] section in the configuration file. If it doesn't exist, add the section at the bottom of the file.
- Add the following line under the [mysqld] section to enable slow query logging: slow_query_log = 1
- Specify the path and name of the slow query log file by adding the following line: slow_query_log_file = /path/to/slow-query.log Replace /path/to/slow-query.log with the desired file location and name.
- To configure the threshold value for slow queries, add the following line: long_query_time = 2 In this example, a query that takes more than 2 seconds to execute will be considered a slow query. Adjust the value as per your requirement.
- Save the changes to the configuration file.
- Restart the MariaDB service to apply the changes: sudo systemctl restart mariadb
Now, MariaDB will start logging slow queries to the specified file. You can analyze the log file to identify and optimize slow queries for better performance.
What is the purpose of the GROUP BY clause in MariaDB on Linux?
The purpose of the GROUP BY clause in MariaDB on Linux is to divide the result set of a query into groups based on one or more columns. It is typically used in combination with aggregate functions, such as SUM, COUNT, AVG, etc., to perform calculations on each group separately. The GROUP BY clause is useful for grouping similar data together and obtaining summarized information from larger datasets.
What is the MariaDB root password by default on Linux?
The MariaDB root password is not set by default on Linux. During the installation process, you will be prompted to set a root password for the MariaDB database server.
How to grant privileges to a user in MariaDB on Linux?
To grant privileges to a user in MariaDB on Linux, you can follow these steps:
- Connect to the MariaDB server as a user with administrative privileges. You can use the following command to log in:
mysql -u root -p
You will be prompted to enter the password for the root user.
- Once you are logged in to the MariaDB server, you need to select the specific database where you want to grant privileges to the user. You can use the following command to switch to the desired database:
database_name with the name of the database you want to grant privileges on.
- Now, you can grant privileges to the user using the GRANT statement. Here's the basic syntax:
GRANT privileges ON database_name.table_name TO 'username'@'localhost';
privileges with the specific privileges you want to grant, such as
DROP, etc. Replace
database_name.table_name with the specific database and table where you want to grant privileges. Replace
username with the name of the user you want to grant privileges to, and
localhost with the appropriate host.
- After executing the GRANT statement, you need to flush the privileges to ensure that the changes take effect. You can use the following command:
That's it! The specified user should now have the granted privileges on the specified database and table.
What is the maximum length of a table name in MariaDB on Linux?
The maximum length of a table name in MariaDB on Linux is generally 64 characters. However, it can vary depending on the specific file system being used. Some file systems may have limitations on the maximum length of a file name or path, which can affect the maximum length of a table name.
What is the purpose of the TRUNCATE statement in MariaDB on Linux?
The purpose of the TRUNCATE statement in MariaDB on Linux is to delete all the data from a specified table, while keeping the table structure intact. This is different from the DELETE statement, which removes specific rows from the table. TRUNCATE is a faster and more efficient method of deleting all the data in a table compared to DELETE, especially when dealing with large tables, as it does not generate individual undo logs for each row deletion. Additionally, TRUNCATE also resets the auto-increment values of the table, whereas DELETE does not.
What is the purpose of the LIMIT clause in MariaDB on Linux?
The purpose of the LIMIT clause in MariaDB on Linux is to restrict the number of rows returned by a SELECT statement. It allows you to specify a limit to the number of rows to be fetched, starting from the first row of the result set. This can be useful for pagination, limiting the amount of data retrieved, or optimizing performance by reducing the amount of data transferred.