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Lesson 3.1 – How Formulas Work

Lesson 3.1 – How Formulas Work Formulas are the core of Excel. They allow you to perform calculations, analyze data, and automate tasks. Every formula in Excel follows a simple structure and always begins with an equal sign (=). Understanding how formulas work is essential before learning specific functions. 1. The Structure of a Formula All Excel formulas follow this basic pattern: =operand operator operand Example: =5 + 3 =A1 * B1 =SUM(A1:A10) Excel calculates the result and displays it in the cell, while the formula remains visible in the Formula Bar. 2. The Equal Sign (=) Every formula must start with = . Without it, Excel treats the entry as text. Examples: =10+5 → Excel calculates 10+5 → Excel shows “10+5” as text 3. Operators in Excel Operators tell Excel what type of calculation to perform. Operator Meaning Example + Addition =A1 + B1 - Subtract...

Lesson 2.5 – Basic Data Cleaning

Lesson 2.5 – Basic Data Cleaning Clean data is essential for accurate calculations, sorting, filtering, and analysis. Even small issues—extra spaces, inconsistent capitalization, or unwanted characters— can cause formulas to fail or produce incorrect results. In this lesson, you will learn simple but powerful tools to clean data quickly using Excel functions. 1. Why Data Cleaning Matters Raw data often contains problems such as: Extra spaces before or after text Inconsistent capitalization Non-printable characters from imported files Mixed formats (text that looks like numbers) Cleaning data ensures consistency and prevents errors in formulas and analysis. 2. TRIM – Remove Extra Spaces TRIM(text) removes extra spaces from text, leaving only single spaces between words. Example: Original: “ Product A ” Formula: =TRIM(A1) Result: “Product A” TRIM is essential when working with imported or manually typed data. ...

Lesson 2.4 – AutoFill and Flash Fill

Lesson 2.4 – AutoFill and Flash Fill AutoFill and Flash Fill are two powerful Excel tools that help you enter data faster and reduce repetitive work. AutoFill extends patterns and formulas, while Flash Fill recognizes patterns automatically and fills the remaining values for you. 1. What AutoFill Does AutoFill uses the small square at the bottom-right corner of the active cell (the Fill Handle ) to copy or extend data. You can use AutoFill to: Copy values Extend sequences (1, 2, 3…) Extend dates (Mon, Tue, Wed…) Copy formulas and adjust references 2. Using AutoFill Steps: Select a cell or a range. Drag the Fill Handle down, up, left, or right. Release the mouse to apply the pattern. Examples: Type January → drag → Excel fills February, March… Type 1 and 2 → select both → drag → Excel continues 3, 4, 5… Type 15/03/2024 → drag → Excel fills the following dates 3. AutoFill with Formulas When you drag a formu...

Lesson 2.3 – Number Formats

Lesson 2.3 – Number Format Number formats control how Excel displays numeric values such as currency, percentages, dates, and measurements. Formatting does not change the underlying value — it only changes how the value appears. Understanding number formats is essential for creating clear, professional spreadsheets. 1. What Number Formats Do Excel stores numbers as raw values (e.g., 1500), but you can display them in different ways: 1,500 → with thousand separators $1,500.00 → as currency 1500% → as a percentage 15/03/2024 → as a date The value stays the same — only the appearance changes. 2. Accessing Number Formats You can apply number formats from: Home → Number group Right-click → Format Cells The Format Cells window provides the most complete set of options. 3. Common Number Formats 3.1 General The default format. Excel displays the number in the simplest way possible. 3.2 Number Used for standard nu...

Part II: Retrieving Data Chapter 4: Advanced Filtering and Expressions

Chapter 4: Advanced Filtering and Expressions In this chapter, we’ll deepen your SQL toolkit by mastering advanced filtering techniques and expressions in the WHERE clause. Precise filters let you extract exactly the rows you need, avoid noisy results, and improve query performance. We’ll cover: Comparison Operators: = , <> , > , < , >= , <= Logical Operators: AND , OR , NOT Pattern Matching: LIKE with % and _ wildcards Set Membership & Ranges: IN and BETWEEN Handling Missing Values: IS NULL and COALESCE By the end, you’ll be crafting tight, readable filters that yield clean, accurate datasets. 1. Comparison Operators Comparison operators form the bedrock of row-level filtering. They compare a column’s value to a constant or another column. Operator Description Example = Equal to WHERE status = 'active' <> Not equal to WHERE rating <> 5 > Greater than WHERE price > 100 < Less than WHERE quantity < 10 >= Greater than or equ...