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SQL Basics, day by day

For Beginners to databases — anyone who has written a little code or lived in spreadsheets and wants to query and shape real data. · 15 days · Tech

A 15-day course
One short lesson a day · go at your own pace
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The days
Listen to the whole course · 72 min
  1. 0Open the SQLite benchBy the end you can install SQLite, create library.db, and run one query against your first table. Listen · 5 min
  2. 1Name the table shapeBy the end you can explain tables, rows, columns, and the SQLite types used by `books`. Listen · 5 min
  3. 2Choose columns with SELECTBy the end you can write `SELECT` queries that return only the columns you need. Listen · 5 min
  4. 3Filter rows with WHEREBy the end you can use `WHERE` to return rows that match a condition. Listen · 5 min
  5. 4Sort and slice resultsBy the end you can use `ORDER BY` and `LIMIT` to control result order and size. Listen · 5 min
  6. 5Add rows with INSERTBy the end you can insert new book rows and verify what changed. Listen · 5 min
  7. 6Change rows safelyBy the end you can use `UPDATE` and `DELETE` with a `WHERE` clause and verify before committing to a change. Listen · 5 min
  8. 7Connect tables with keysBy the end you can create `members` and `loans` tables and use ids to connect rows. Listen · 5 min
  9. 8Join related rowsBy the end you can use `JOIN` to combine `books`, `members`, and `loans` into one readable result. Listen · 5 min
  10. 9Summarize with aggregatesBy the end you can use `COUNT`, `SUM`, `AVG`, `MIN`, and `MAX` to summarize rows. Listen · 5 min
  11. 10Group rows by keyBy the end you can use `GROUP BY` and `HAVING` to summarize rows per category. Listen · 5 min
  12. 11Handle NULL on purposeBy the end you can query `NULL` values with `IS NULL` and explain why normal equality does not work. Listen · 5 min
  13. 12Protect data with constraintsBy the end you can create a constrained `holds` table with primary keys, required values, checks, and foreign keys. Listen · 5 min
  14. 13Speed lookups with indexesBy the end you can create an index and read a simple query plan that uses it. Listen · 5 min
  15. 14Answer library questionsBy the end you can combine filtering, joining, grouping, `NULL` handling, and sorting to answer real library questions. Listen · 5 min