MariaDB Interview Questions | Freshers & Experienced

MariaDB is a popular public source under GNU GPL which is related to database management technology developed by MySQL developers. Basically, it is the modification of MySQL that is more scalable, speedy, and easy to hand in and also provides a lot of services like the plugin, storage, and much more.

Some of the features of MariaDB are as follows:

• It provides a great number of storage engines.
• It provides some great extraordinary performance engines.
• It has a good paradigm inquiring language.
• It supports a lot of operating systems and can work on them.
• It supports a large number of programming languages.
• It even supports the most used web development language that is PHP.
• Galera cluster technology is also supported by MariaDB.

The syntax to create a Database in MariaDB is CREATE DATABASE. Syntax - create [or replace] database [if not exists] database_name

Michael “Monty” Widenius is the founder of MariaDB as well as the founder of MYSQL. The main focus of the MariaDB Foundation is to keep the quality of the MariaDB project high.

The difference between MariaDB & Mysql can be stated as MySQL is open-source relational database management developed by oracle which is used in many small and large-scale industrial applications and is capable of handling a large volume of data. Whereas MariaDB is an open-source relational database management system developed by MariaDB Foundation, developed as the replacement of MySQL as it is consists of a significantly high number of new features, which makes it better in terms of performance and user orientation.

In MariaDB, the stored procedures are basically the procedures that work as a stored program in which a particular type of parameter is allowed to pass through them but in exchange, they do not return any value.

There are three types of procedures available in the MariaDB database on the basis of references and parameter overwritten, which are as follows:

IN procedure- In this type of procedure, the values of a parameter can be overwritten and referenced by the procedure.

OUT procedure- In this type of procedure, the values of parameters can be overwritten by the procedure but it can’t be referenced by a procedure.

IN OUT- In this type of procedure, the values of a parameter can be referenced by the procedure but they can’t be overwritten by a procedure.

There are basically two types of JOIN present in MariaDB. These are as follows:

Inner join - Inner join is a type of join that works only when the conditions are satisfied. It is used to recover the rows from two or more tables.

Outer join - It can be categorized as:

• LEFT JOIN - It works on those rows in a table where the particular conditions are satisfied. LEFT OUTER JOIN is basically useful at the time of recovering those rows which have to be carried from the left-hand table but in ON condition. It is also referred to as LEFT OUTER JOIN.
• RIGHT JOIN - It is also known as RIGHT OUTER JOIN and works on those rows in a table where the particular conditions are satisfied. RIGHT OUTER JOIN is basically useful at the time of recovering those rows which have to be carried from the right-hand table but in ON condition.

Some of the important tools of Gui/workbench for MariaDB Aria are as follows:

• Webyog/SQLyog
• HeidiSQL
• dbForge Studio for MySQL
• MySQL Workbench.

When the table is not compressed, MariaDB writes to a shared temporary tablespace as defined by the innodb_temp_data_file_path system variable.

In MariaDB, the LIKE clause is used with the SELECT statement to retrieve data when an operation needs an exact match.

You can create a table alias in MariaDB with the help of the following steps:

• First of all, it needs to construct a database.
• When it is done, select the database.
• After that create a table by commanding CREATE TABLE statement.
• If you want to create or delete the table you must have the privilege of it.

In MariaDB, the TRUNCATE command is used only when the whole table has to be deleted or removed permanently. It is faster and also kept the record in the transaction log but it firstly eliminates the data by deallocating it which is efficient to store and record.

In MariaDB, the SUM() function is used to sum all values in the expressions and returns the final result. In case, if there are no values in the expressions, then it returns a null value. Syntax - Select SUM from tables were conditions.

Some of the aggregate functions available in MariaDB is as follows:

AVG - Returns the average value.

BIT_AND - Bitwise AND.

BIT_OR - Bitwise OR.

BIT_XOR - Bitwise XOR.

COUNT - Returns the count of non-null values.

COUNT DISTINCT - Returns the count of a number of different non-NULL values.

GROUP_CONCAT - Returns a string with concatenated values from a group.

MAX - Returns the maximum value.

MIN - Returns the minimum value.

STD - Population standard deviation.

STDDEV - Population standard deviation.

STDDEV_POP - Returns the population standard deviation.

STDDEV_SAMP - Standard deviation.

SUM - Sum total.

VARIANCE - Population standard variance.

VAR_POP - Population standard variance.

VAR_SAMP - Returns the sample variance.