SQL Essentials: UPPER and LOWER Functions Explained

Overview

The UPPER and LOWER functions are text transformation tools that allow you to convert text to a specific case, either uppercase or lowercase, respectively. These functions are essential for data normalization and consistency, ensuring that your data is uniform and easily searchable.

In simple terms, UPPER transforms any text into all capital letters, while LOWER changes text into small letters. This is particularly useful when dealing with data entered by different users or imported from various sources, as it helps standardize the information.

Understanding the Syntax

UPPER(text)

LOWER(text)

In these functions, 'text' refers to the field or expression containing the text you want to convert.