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Hello guys, If you're preparing for SQL interviews or working on real-world reporting tasks, mastering window functions is no longer opt...

PostgreSQL is one of the most popular databases after the big three - Oracle , SQL Server , and MySQL . PostgreSQL is commonly known as Pos...

Hello guys,  I am feeling proud and excited to announce the release of my new book, "Grokking the SQL Interview" , a book, which ...

Hello guys, If you have joined any course on Udemy then I am sure you will have your favorite instructor, I have many and in the past I have...

Hello guys, if you are learning Data Science and Machine Learning in 2025 and looking for essential tools and libraries then you have come ...

Since a primary key is nothing but a constraint, you can use the  ALTER clause of SQL to add a primary key into the existing table. Though...

You can increase the length of a VARCHAR column without losing existing data in SQL Server. All you need to do is execute the following ALT...

Hello guys, you might know that along with Oracle and MySQL, Microsoft SQL Server is one of the most popular relational databases in the te...

Hello guys, if you want to learn Oracle SQL and look for free online courses, you have come to the right place. Earlier, I shared the best S...

If you an experienced programmer and know how to write SQL queries and database fundamentals but want to take your SQL and database skills ...

In last summer, I had to work on a Java project which was using the Oracle database at their backend. The project was a mix of Java code wi...

Hello guys, we are already in the second week of New year, and everyone is talking about their goals to improve them as a better person, a ...

Hello guys, if you are interested in learning SQL with MySQL database and looking for some awesome resources e.g. books, tutorials, and onl...

Hello guys, if you are a computer science graduate or new to the programming world, interested in learning SQL, and looking for some excell...

Problem, I was doing join statement and getting this error Msg 4104, Level 16, State 1, Line 69 The multi-part identifier "a.X" co...

SQL is one of the most important skills for any programmer be it a Java , C++ , Python , JavaScript , or Ruby developer. Almost 95% of the J...

We often need to replace NULL values with empty String or blank in SQL e.g. while concatenating String. In SQL Server, when you concatenate...

What is the difference between char and varchar in SQL, followed by nchar and nvarchar , is one of the popular SQL interview questions , an...

The database design and modeling are one of those topics which rarely get the attention they deserve, especially at the start of the projec...

Hello guys, if you are wondering how to find duplicate values in a table then don't worry, there are many ways to find duplicate rows or...