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← Build things with code · Mission 17 of 18

Analyse a million-row spreadsheet in seconds, when Excel gives up

Open a 2-million-row sales file in Excel and it quietly stops at row 1,048,576: 951,425 sales gone, and every total wrong. DuckDB reads the whole file and answers in under half a second, then hands the answers back as a small Excel sheet. By the end you'll have a monthly report you can sell to any business sitting on exports it never looks at.

75 minBeginnerTools: FreeStep 1 free
Tested 9 Oct 2026 · DuckDB 1.5.6 installed with winget, a 2-million-row practice CSV, Excel 16.0 for the comparison, Windows 11
DuckDB installeda free program that reads huge CSV and Excel files straight off your disk
Answers from 2 million rows in under half a secondsales by month, by store, top products and profit
Your answers saved as a CSV or a real Excel .xlsx file you can send to someone
  • A tested starter pack of 18 business queries to copy, paste and reuse
  • A messy real-world till export cleaned with SQL that AI writes for you, and the checks that catch its mistakes
  • A sellable monthly report: one script per client, one tidy Excel workbook, plus who to sell it to
Before you start
  • Windows, Mac or Linux, and about 200MB of free disk space (350MB if you also try the optional browser app)
  • No SQL experience. Every query in this mission is copy and paste
  • Helpful but not required: Level 0's terminal survival kit
01/09Install DuckDB0 done
STEP 01 of 09~3 min

Install DuckDB

DuckDB is a free, open-source program that answers questions about data files. One small download, no admin rights.

  1. Think of DuckDB as a calculator for big files. Instead of opening a file and scrolling, you ask a question in a line or two of SQL (the language databases understand), and it reads the file and prints the answer. Asking questions only reads your file. It never changes it.

    Windows
    winget install --id DuckDB.cli -e --scope user
    Mac (with Homebrew)
    brew install duckdb
    Linux (or Mac without Homebrew)
    curl https://install.duckdb.org | bash

  2. On Windows, winget downloads the official 12.9MB zip from DuckDB's GitHub releases and unpacks it into your user folder (the program itself is 37MB). It takes a few seconds and needs no admin rights:

    Output
    Found DuckDB CLI [DuckDB.cli] Version 1.5.6
...
Successfully verified installer hash
Extracting archive...
Successfully extracted archive
Starting package install...
Path environment variable modified; restart your shell to use the new value.
Command line alias added: "duckdb"
Successfully installed

  3. On Linux and Mac, the install script puts DuckDB in ~/.duckdb/cli and prints an export PATH=... line at the end: paste that line into your terminal (and add it to ~/.bashrc or ~/.zshrc to keep it). Then close the terminal, open a new one, and check it's there:

    Terminal
    duckdb --version
    Output
    v1.5.6 (Variegata) 069cc9f9b5
✓
Checkpointduckdb --version prints a version number.
If it breaks'duckdb' is not recognised as the name of a cmdlet + 1 more
'duckdb' is not recognised as the name of a cmdlet
The install changed your PATH, but only new windows see it (winget even says "restart your shell"). Close every terminal window and open a fresh one.
'winget' is not recognised
Update App Installer from the Microsoft Store and try again. Or download duckdb_cli-windows-amd64.zip from the DuckDB releases page ↗, unzip it, copy duckdb.exe into your data folder (next step) and type .\duckdb instead of duckdb.
Still stuck? Ask the community
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