10+ Interview Questions and Answers

Use SQL JOIN to combine two tables and display information.

• Use the JOIN keyword to combine tables based on a related column

• Specify the columns you want to display in the SELECT statement

• Use ON clause to specify the column used for joining the tables

Print numbers in pyramid shape patterns using SQL code.

• Use a loop to iterate through rows and columns to print the numbers in pyramid shape.

• Increment the numbers in each row to create the pyramid effect.

• Consider the spacing and alignment to create a visually appealing pyramid pattern.

List is a collection of objects, string array is an array of strings, etc. Each has its own characteristics and uses.

• List: dynamic collection of objects, can grow/shrink in size. Example: List numbers = new ArrayList<>();

• String array: fixed-size array containing strings. Example: String[] names = new String[3];

• Array: fixed-size collection of elements of the same type. Example: int[] scores = new int[5];

Code to sort array without sort function

• Iterate through the array and compare each element with the rest to find the smallest element

• Swap the smallest element with the first element in the unsorted portion of the array

• Repeat the process for the remaining unsorted portion of the array until fully sorted

Object-oriented programming concepts that focus on classes, objects, inheritance, encapsulation, and polymorphism.

• Classes: Blueprint for creating objects with attributes and methods.

• Objects: Instances of classes that contain data and behavior.

• Inheritance: Ability for a class to inherit attributes and methods from another class.

• Encapsulation: Bundling data and methods that operate on the data into a single unit.

• Polymorphism: Ability for objects of different classes to respond ...read more

SQL join types allow combining data from multiple tables based on a specified condition.

• Inner Join: Returns rows that have matching values in both tables.

• Left Join: Returns all rows from the left table and the matched rows from the right table.

• Right Join: Returns all rows from the right table and the matched rows from the left table.

• Full Outer Join: Returns all rows when there is a match in either left or right table.

• Self Join: Joining a table with itself to combine rows base...read more

Different types of joins in SQL include inner join, outer join, left join, right join, and full join.

• Inner join: Returns rows when there is a match in both tables

• Outer join: Returns all rows from one table and only matching rows from the other table

• Left join: Returns all rows from the left table and the matched rows from the right table

• Right join: Returns all rows from the right table and the matched rows from the left table

• Full join: Returns rows when there is a match in one...read more

Key types in SQL include primary keys, foreign keys, unique keys, and composite keys.

• Primary key: uniquely identifies each record in a table.

• Foreign key: establishes a relationship between two tables.

• Unique key: ensures that all values in a column are unique.

• Composite key: combination of multiple columns to uniquely identify a record.

Ci/cd pipeline automates the process of building, testing, and deploying code changes.

• Automates code integration, testing, and deployment

• Ensures consistency and reliability in software delivery

• Facilitates faster feedback loops for developers

• Examples: Jenkins, GitLab CI/CD, Azure DevOps

DBMS is a software system that manages databases, while RDBMS is a type of DBMS that stores data in a structured format using tables.

• DBMS stands for Database Management System, which is a software system that manages databases.

• RDBMS stands for Relational Database Management System, which is a type of DBMS that stores data in a structured format using tables with relationships between them.

• RDBMS uses SQL for querying and managing data, while DBMS may or may not support SQL.

• Exa...read more