The name NoSQL itself tells us that it is a  "non-SQL"  or  "non-relational"  database. Around 30 years back when the data used to be non-changing and smaller in size, traditional relational databases were more prominent like ORACLE, Postgres and so on which had fixed schemas. But during the last decade, the data has grown exponentially and it is also changing quickly. The traditional databases have failed to handle this BIG DATA effectively. So there was a need to introduce a database that can adapt itself to ever-changing data and that can handle the enormous size of data. And thus NoSQL databases came into the picture. Nowadays NoSQL databases have been referred to as  "Not Only SQL"  databases which mean that these databases may support SQL-like query languages and can be a part of polyglot persistent architecture along with other relational databases. The data structures used in the NoSQL database are more efficient than the data structures used by th...

You might be using Union or Union All in your SQL code while doing Data Analysis or building Data Pipelines. Ever wondered what is the difference between them and how using one over another can be more efficient? Yes, there is a small yet significant difference between Union and Union All. Let's look at that by understanding each of them individually. 1. Union All  Union All basically allows you to concatenate the table that has a similar structure of tables. The important condition to have Union All of the tables is that both the tables should have the same number of columns. So when you take Union All of two tables what it does in the background is it directly joins the tables without removing duplicates or redundant records.   2. Union  Union is also similar to Union All except one difference that it removes the duplicates records before taking the Union of the tables.  There is one disadvantage of Union over Union All, that since it removes duplicated records bef...