What is Database? It is used to collect and store the data using structured and unstructured patterns. the database provides different rules to store and manage data. 1) DBMS:-  It provides storage of data using file pattern, we can not establish a relationship between files and records. MS-Excel, XML 2) RDBMS: It means relational database management system, it provides a set of rows and columns to store data means it provides a database table to store and manage records. We can establish relationships between tables and database objects. Name of RDBMS Software:- 1) Oracle  2) MYSQL 3) MS-SQL 4)  PostgreSQL 5)  IBM DB2 3)  ORDBMS:-  It means Object-Relational Database Management System. It provides storage of data using object patterns we can perform all operations under objects to manipulate the data. ORDBMS Tools:- Mongo DB is the database software tool to implement in Object patten Oracle Object & Forms 4)  CDBMS:-   CDBMS means a ...

 Most Important SQL Query for Interview:- 1)  Write Query to add and remove a new column in tables? 2)  Write a Query to add a primary Key into a table? 3)  Write a Query to add a foreign key in a table? 4)  Write a Query to rename the table, database, and column? 5)  Write q Query to implement self join, inner join, outer join, and natural join? 6)  Write a Query to use Group by and having Most Important SQL Query for Interview:- Dept(Deptid, Deptname) Emp(Empid,Empname, Job, Salary, Deptid) 7)  WAQ to display total employee and each dept? 8)  WAQ to display the record of the employee who is getting second max salary? 9)  WAQ to select deptname and job where number of employee is more then 3? 10)  WAQ to  display max, min,avg salary on each dept excluding IT dept? 11) WAQ to display the name of dept where employee is null? 12) WAQ to display the empname whose salary is minium?

Most important SQL Query under MYSQL Database for developers:- If you are directly read this article then first read the following article for database knowledge, you can learn database fundamentals after that you can learn SQL easily. Article for database fundamentals:- https://www.shivatutorials.com/2020/08/database-tutorials-sql-tutorials-mysql.html Article for MYSQL Fundamentals:- https://www.shivatutorials.com/2020/08/mysql-for-developers.html Now many GUI tools have provided by many database software such as MYSQL ( MYSQL YOG, PHPMYADMIN) Oracle ( SQL Developer), and MS-SQL(Management Studio). But if you create an application then you should knowledge of basic SQL Command and SQL Query. SQL Command has been divided into four different languages. 1) DDL(Data definition language):- It is used to create a database structure and table structure to store records, in the case of Oracle database structure will be managed by user's and oracle server provide default tablespace to mana...

MySQL for Developers:- Before reading this you should read the following articles related to the database. https://www.shivatutorials.com/2020/08/database-tutorials-sql-tutorials-mysql.html  If you are Web Developers or Desktop Developers then you should have knowledge of MYSQL Commands, Methods, and Operator to perform database operation. When you create a database of any software then first you should know about table implementation. Now MYSQL Provide GUI tools using this we can easily create database and table structure, you can easily create Primary Key, Foreign-Key, Index, etc. If you are PHP or Java Developer then you can use PHPMYADMIN or MYSQL Yog Software tools of MYSQL. When you work on PHP Software or Web development then XAMPP, WAMP, MAMP this software by default has MYSQL Server. then no need to install MYSQL separately.

What is Mongodb? ......................................... It is NOSQL based database package that provide easy database based system. without using SQL language we can create database and tables. Documents means record Collection means table if we insert document then collection automatically created. Syntax to create database use Databasename; Syntax to insert record db.collectionname.insertOne({"columnname":"value",...}) Syntax to view all record db.collectionname.find() Syntax to update record db.collectionname.updateOne({"colname":"value"},{$set:{"colname":"value1",...}); Syntax to delete record db.collectionname.remove({"colname":"value"}); What is Mongodb? ......................................... It is NOSQL based database package that provide easy database based system. without using SQL language we can create database and tables. Documents means record Collection means table if we insert document ...