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SQL / CHAPTER 02

SQL
Reports & joins.

Learn SQL with real tables and PostgreSQL in your browser. Learn and Practice per topic, separate challenges.

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SQL

10 lessons available

The foundations behind your ideas.

  1. 01

    COUNT and NULL · Locked

    COUNT and NULL

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  2. 02

    SUM, AVG, MIN, MAX · Locked

    SUM, AVG, MIN, MAX

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  3. 03

    Grouping · Locked

    Grouping

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  4. 04

    Filtering groups · Locked

    Filtering groups

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  5. 05

    Keys and relationships · Locked

    Keys and relationships

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  6. 06

    INNER JOIN · Locked

    INNER JOIN

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  7. 07

    LEFT JOIN · Locked

    LEFT JOIN

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  8. 08

    Rows without a match · Locked

    Rows without a match

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  9. 09

    Counting after a JOIN · Locked

    Counting after a JOIN

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  10. 10

    Customer report · Locked

    Customer report

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SQL · Reports & joins | Code Lab | Calculators BG