Comparing Calculations in Spreadsheets and SQL

1. Calculations Across Tools

Data analysts perform calculations in:

• Spreadsheets (Excel, Google Sheets)
• SQL databases

Although syntax differs, the underlying mathematical logic remains the same.

Understanding the similarities helps analysts transition between tools efficiently.

2. Arithmetic Operators

An operator is a symbol that specifies a mathematical operation.

2.1 Common Arithmetic Operators (Spreadsheets & SQL)

These operators behave identically in both spreadsheets and SQL.

3. Basic Calculations in SQL

Example: Adding Two Columns

Suppose we have columns:

• columnA
• columnB

SQL query:

SELECT 
  columnA,
  columnB,
  columnA + columnB AS total_sum
FROM table_name;

SELECT 
  columnA,
  columnB,
  columnA + columnB AS total_sum
FROM table_name;

Explanation:

• columnA + columnB performs addition.
• AS total_sum names the new calculated column.

4. Using Multiple Operators

If multiple operations are involved, use parentheses to control order of operations.

Example:

SELECT 
  (columnA + columnB) * columnC AS computed_value
FROM table_name;

SELECT 
  (columnA + columnB) * columnC AS computed_value
FROM table_name;

Order of execution:

1. Add columnA and columnB.
2. Multiply result by columnC.

Parentheses ensure correct precedence.

5. Modulo Operator

Purpose

Returns the remainder after division.

SQL Syntax

SELECT columnA % columnB AS remainder
FROM table_name;

SELECT columnA % columnB AS remainder
FROM table_name;

Spreadsheet Equivalent

In spreadsheets:

=MOD(A1, B1)

Modulo is useful for:

• Determining even vs odd numbers
• Cycle-based calculations
• Partitioning data

6. Functions vs Operators

Both spreadsheets and SQL support:

• Direct operators (+, -, *, /)
• Functions (SUM, AVG, etc.)

7. SUM in SQL and Spreadsheets

Spreadsheet

=SUM(A1:A10)

SQL

SELECT columnA % columnB AS remainder
FROM table_name;

SELECT columnA % columnB AS remainder
FROM table_name;

Both return the total of selected values.

8. Average Function

Spreadsheet

=AVERAGE(A1:A10)

SQL

SELECT AVG(columnA) AS average_value
FROM table_name;

SELECT AVG(columnA) AS average_value
FROM table_name;

Both calculate the mean.

9. Aggregate Functions in SQL

In SQL, functions like:

• SUM()
• AVG()
• COUNT()
• MIN()
• MAX()

Are called aggregate functions.

Definition:
Aggregate functions operate on multiple rows and return a single value.

These are commonly used with:

GROUP BY

GROUP BY

To compute grouped summaries.

10. Key Differences Between Spreadsheet and SQL Calculations

11. When to Use Each Tool

Use Spreadsheets When:

• Dataset is small.
• Quick exploration is needed.
• Visual formatting matters.
• Ad hoc analysis is sufficient.

Use SQL When:

• Dataset is large.
• Data resides in database.
• Aggregation across millions of rows is required.
• Multi-table joins are needed.

12. Order of Operations

Both SQL and spreadsheets follow standard mathematical precedence:

1. Parentheses
2. Multiplication/Division
3. Addition/Subtraction

Always use parentheses when logic must be explicit.

13. Practical Insight

Example business calculation:

Revenue formula:

SELECT quantity * unit_price AS revenue
FROM sales;

SELECT quantity * unit_price AS revenue
FROM sales;

Profit formula:

SELECT quantity * unit_price * margin AS profit
FROM sales;

SELECT quantity * unit_price * margin AS profit
FROM sales;

SQL allows these calculations at scale across millions of rows instantly.

14. Summary

Key takeaways:

• Arithmetic operators behave the same in spreadsheets and SQL.
• SQL uses SELECT to compute derived columns.
• Parentheses control calculation order.
• Modulo operator % returns remainders.
• Aggregate functions (SUM, AVG) operate across rows.
• SQL calculations scale to large datasets.
• Understanding both environments increases analytical flexibility.

Mastery of arithmetic operations across tools strengthens foundational analytical skills and prepares analysts for more advanced aggregation and modeling.