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 Hello, and welcome to the blog. Today we are going to talk about " Anomalies in Database ". From this blog we are going to talk more about creating a database that can be used as a project and understanding more about structuring database tables in more efficient way. For that we have to have first understand what things we can do wrong while creating tables. That's why we have started with "Anomalies". Anomalies generally means flaws in the existing system. I think I am done with the overview, now let's see what we are going to cover up today: What is anomalies? Types of Anomalies Insert Update Delete let's begin with 1) What is anamolies? Anomalies are nothing but problems that can occur in poorly planned database. Generally in poorly designed database people try to put many columns in a single table. In our dat...

Hello, and welcome to the blog. In this blog we are going to talk about " Subqueries ". In the  previous blog  we have seen small topic of ALL, IN, ANY operators. Now we will see how write a query inside a query. Don't worry I will elaborate how we are gonna do it. So, we are going to talk about What is Subquery? Rules of writing outer query. Rules of writing subquery. Basic types of Subquery. Correlated Subquery. Possible number of nesting in Subquery Subquery in Update, Delete and Insert Statement Subquery with Exists keyword. let's jump into it 1) What is a subquery Subquery is a query inside a query or you can say it as nested query. It is mainly used as a part of where clause. Subquery returns data that will be used in the main query. Subquery can be used with SELECT, INSERT, UPDATE and DELETE statements. ...