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SQL Basics

Practical SQL for industrial and energy professionals who need to answer their own data questions: reading relational tables, writing SELECT queries with filters, groups and joins, and querying production systems safely and read-only.

55m
Total time
4
Competency levels
12
Lessons

What you'll learn

  • Describe how relational data is organised into tables, rows, columns, primary keys and foreign keys
  • Write SELECT queries using WHERE, GROUP BY, HAVING, ORDER BY and row limits
  • Explain the difference between the written clause order and the logical evaluation order of a query
  • Handle NULL values correctly and avoid the comparison traps they create
  • Choose between inner and left joins, and recognise duplicate and cross-join row explosions
  • Apply read-only discipline on production databases and share queries others can trust and reuse

Curriculum

Progress through each competency level in order.

1

Awareness

  • How Relational Data Is Organised
    Knowledge
    3m
  • The Anatomy of a SELECT Statement
    Knowledge
    3m
  • Awareness Check: Tables and SELECT
    Assessment
    7m
2

Knowledge

  • Filtering Rows: WHERE, IN, LIKE, BETWEEN and NULL
    Knowledge
    3m
  • Aggregation, GROUP BY, HAVING and Logical Evaluation Order
    Knowledge
    3m
  • Knowledge Check: Filtering and Grouping
    Assessment
    8m
3

Skill

  • Joins, Duplicates, Sorting and Limits
    Knowledge
    3m
  • Answer a Real Question with a Query Set
    Assignment
    3m
  • Skill Check: Joins and Result Sets
    Assessment
    8m
4

Mastery

  • Querying Production Safely and Sharing Work Others Can Trust
    Knowledge
    3m
  • Publish a Reviewed, Reusable Query Pack
    Assignment
    3m
  • Mastery Check: Safe, Trustworthy Querying
    Assessment
    8m

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