Knowing SQL Query Language

Understanding the syntax of SQL queries is important before we get into the specifics of turning them into Lambda expressions. Most SQL queries are made up of various components, including:

1. SELECT: This clause defines which database columns should be retrieved.
2. From: The FROM clause defines which table or tables should be used to retrieve the data.
3. WHERE: This clause outlines any prerequisites that must be satisfied in order for a row to be returned by the query.
4. GROUP BY: Using one or more columns, this clause groups the result’s rows.
5. HAVING: This clause outlines any prerequisites that groups in the outcome must satisfy.
6. ORDER BY: This phrase outlines the sequence in which the result’s rows should be displayed.

Lambda expressions make it simple to define anonymous functions in computer languages. Functions can be used as arguments or returned as values in functional programming paradigms, where they are treated as first-class citizens.

Lambda expressions let you declare a plain function “inline”—without giving it a name—when it has to be written and will only be called once. They are also a great way to streamline your code and make it clearer and more expressive.

In many programming languages, lambda expressions are distinguished by the “lambda” keyword, a list of parameters that are separated by commas, a colon, and the expression that will be evaluated.