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10: Getting started with MySQL database beginner tutorial

All Java developers not only must know “SQL”, but also a database is required for “JDBC tutorials”, “Hibernate Tutorials”, and so on. Any decent Java application will require a database.

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14+ SQL beginner interview Q&As

SQL interview Questions & Answers is a must for any developer as all non-trivial applications need to talk to a database with CRUD operations. Q3 – Q15 are very popular...

15 Database design interview Q&As

Q1. What is normalization? When to denormalize? A1. Normalization is a design technique that is widely used as a guide in designing relational databases. … Read more ›...

15+ SQL optimisation interview questions & answers with scenarios

1) Select fields instead of using SELECT *. The “*” is used as a short hand to query all available data from a table. … Read more ›...

15+ SQL scenarios based interview Q&As – part 1

Q01 How will you go about identifying duplicate records in a table?
A01 This is a very popular interview question because there are many approaches,

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15+ SQL scenarios based interview Q&As – Part 2

This extends Q01 – Q03 at 15+ SQL scenarios based interview questions answered. Q04 When you have a table that maintains history of record updates, … Read more ›...

15+ SQL scenarios based interview Q&As – Part 3

This extends 15+ SQL scenarios based interview Q&As – Part 2. Q07 In What order the SELECT SQL statements are executed? … Read more ›...

18 SQL best practices interview Q&As

#1. Use uppercase for the keywords like SELECT, FROM, JOIN, GROUP BY, WHERE, etc. It’s also a good practice to use uppercase for the SQL functions like UPPER(col_name),

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Auditing database record changes in Oracle

Q. What are some of the considerations in auditing database table data? A. Creating audit tables without any constraints to store record changes. … Read more ›...

Common Table Expressions (i.e. CTE) in SQL using the “WITH” clause

Common Table Expressions or CTE’s for short are used in SQL to simplify complex joins and subqueries, and to provide a means to query hierarchical data such as an organisational...

Deleting records in SQL Interview Questions and Answers

The following is a very popular SQL job interview question. Q. What is the difference between “Truncate” and “ … Read more ›...

SQL analytic functions interview questions – Part 1

Data Engineers & analysts must know the analytic functions applied over a window of rows is a powerful tool to analyse the data. This post compliments “Apache Spark window functions”...

SQL analytic functions interview questions – Part 2

This extends SQL window function for analytical queries interview questions – Part 1 Analytic function construct The analytic function names can be RANK(), … Read more ›...

SQL analytic functions interview questions – Part 3

This extends SQL analytic functions interview questions – Part 2 and SQL analytic functions interview questions – Part 1. The below example was created in IMPALA SQL engine with Common...

SQL querying Temporal tables & SCD Type 2

Q1. What is a temporal table? A1. Temporal tables store and maintain information with respect to time. … Read more ›...

SQL retrieving the latest records interview Q&As

This question can reveal a lot about your ability to write SQL queries as different approaches can be used and there will be drill down on pros and cons of...

SQL Subquery interview questions and answers

Q. What is a subquery?
A. Subquery or Inner query or Nested query is a query in a query. A subquery is usually added in the WHERE clause of the sql statement.

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Transaction management in SQL — Sybase example

Q. How do you perform transaction management in SQL stored procedures?
A. Handled with begin, commit, and rollback ‘

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800+ Java Interview Q&As