What is a Nested Select Statement?

What is a Nested Select Statement?

In PostgreSQL, a Nested query is a query within another PostgreSQL query and embedded within the WHERE clause. It is also known as a subquery, which is a query nested within another query....

How to Write or Define a Subquery in Postgres?

Here’s the syntax for nested select statements in PostgreSQL:...

Examples of Nested Select statement in PostgreSQL

To understand What is Nested select statement in PostgreSQL we need a table on which we will perform various operations and queries. Here we will consider a table called employees which contains id, name, salary, and department as Columns....

Conclusion

Overall, the nested select statements in PostgreSQL offer a versatile approach to retrieving data by embedding one query within another. These subqueries can be used in various parts of a SQL query, such as the SELECT, FROM, WHERE and HAVING clauses, providing flexibility in data retrieval. Through examples, we’ve learnt how nested select statements can be used to filter results, calculate aggregate functions, perform comparisons, and retrieve top records....