Posts in 2024
  • Authentication, Authorization

    Thursday, June 13, 2024 in Spring Interview Questions

    Authentication, Authorization Authentication The process of verifying the identity of a user Authorization The process of verifying what an authenticated user is allowed to do

    Read more

  • Math

    Thursday, June 13, 2024 in LeetCode Notes

    Starred by 25+ users, GitHub Repo: LeetCode Pattern 500 offers: 500 solutions for LeetCode problems in Python and Java 17 notes on essential concepts related to data structures and algorithms 130 patterns for solving LeetCode problems math intro …

    Read more

  • Lombak

    Thursday, June 13, 2024 in Spring Interview Questions

    Lombak @Data annotation on POJO to generate boilerplate code such as getters, setters, toString, equals, and hashCode methods

    Read more

  • Delete Data In Table

    Thursday, June 13, 2024 in SQL Server Interview Questions

    Delete Data In Table -- without a join DELETE FROM comments WHERE commentID = 2; -- with a join DELETE comments FROM comments INNER JOIN posts ON comments.postID = posts.postID WHERE posts.title = 'First Post'; 196. Delete Duplicate Emails /* …

    Read more

  • Checked Exceptions vs Unchecked Exceptions

    Thursday, June 13, 2024 in Java Interview Questions

    Checked Exceptions vs Unchecked Exceptions Checked Exceptions Unchecked Exceptions Definition Exceptions that are checked at compile-time Exceptions that occur at runtime and are not checked at compile-time Handling Requirement Must be either caught …

    Read more

  • Update Data In Table

    Thursday, June 13, 2024 in SQL Server Interview Questions

    Update Data In Table UPDATE posts SET title = 'Updated First Post' WHERE postID = 1; 627. Swap Salary /* Write your T-SQL query statement below */ UPDATE Salary SET sex = CASE sex WHEN 'm' THEN 'f' ELSE 'm' END;

    Read more

  • Object-Relational Mapping (ORM)

    Thursday, June 13, 2024 in Spring Interview Questions

    Object-Relational Mapping (ORM) ORM provides the foundational concept for mapping objects to relational databases Java Persistence API (JPA) standardizes ORM in Java, defining a set of rules and interfaces Hibernate implements JPA, offering the …

    Read more

  • Greedy

    Thursday, June 13, 2024 in LeetCode Notes

    Starred by 25+ users, GitHub Repo: LeetCode Pattern 500 offers: 500 solutions for LeetCode problems in Python and Java 17 notes on essential concepts related to data structures and algorithms 130 patterns for solving LeetCode problems greedy intro …

    Read more

  • == vs equals vs hashCode

    Thursday, June 13, 2024 in Java Interview Questions

    == vs equals vs hashCode == equals hashCode Definition Compares references for objects, values for primitives Compares the contents of two objects Returns a hash code value for the object Good Practice Always override equals() when a class’s …

    Read more

  • String vs StringBuilder vs StringBuffer

    Thursday, June 13, 2024 in Java Interview Questions

    String vs StringBuilder vs StringBuffer String StringBuilder StringBuffer Mutability Immutable Mutable Mutable Thread Safety Thread-safe Not thread-safe Thread-safe Use Case Suitable for values that won’t change Best for strings that are …

    Read more