Friday, January 28, 2022

Top 15 SQL Query Interview Questions for Practice

 Hello folks, if you are preparing for technical interviews for software developer, system admin, data analyst, or data scientist, one skill you must prepare is SQL. It's the declarative langauge that allows you to interact with the database. By using SQL you can insert, update, search, and delete data in a relational database. 

The code you write is called SQL queries and it's one of the essential skills for many technical people who have to deal with databases. That's why SQL queries are very popular in interviews and you will often see one or more SQL queries on interviews. 

They are not just popular in the telephonic or face-to-face interviews but also during the written tests and that's why it's become imperative for developers, DBAs, and Data scientists to practice SQL queries during coding interview preparation. Here are some SQL queries you can practice for SQL and Database interviews:

Wednesday, January 26, 2022

How to concatenate columns in SQL Server? Example Tutorial

Hello guys, welcome to my new blog SQLrevisited. I have long back created this blog to exclusively share SQL and Database articles but never get time to start it until today. This is the first article on this blog and in this post, you will learn how to contact multiple columns in an SQL server. 

Like Java and many other programming languages and databases, you can use the + operator to concatenate multiple columns in SQL Server. You can join as many columns as you want with the + operator but you must remember that concatenating with NULL will produce NULL, which means you can lose the information from other columns if one of them is NULL.