Analytical Functions: Defining Custom Window Frames

ROWS BETWEEN n1  PRECEDING and n2  FOLLOWING Let's consider a table shown i…

Analytical Functions: Calculating Running Totals

Imagine a situation where you're managing a score keeping system for games.…

Analytical Functions: OVER and PARTITION BY

Oracle SQL functions can be categorized into three main types: scalar, aggregat…

Conditional Expressions in a SELECT Statement

In programming languages, conditional expressions refer to structures that crea…

Common Table Expressions: The WITH Clause

Correlated Subqueries

Subqueries typically have syntactical autonomy, meaning that they can be execut…

Subquery Basics

What Are Subqueries? As its name implies, SQL, the Structured Query Language ,…

Database Normalization

Set Operations in Oracle

In mathematics, there are three key operations between two sets: union, interse…

Table Joins

In a relational database, it is commonly regarded as a best practice to distrib…