WISE OWL EXERCISES
- Simple Queries (4)
- Setting criteria using WHERE (5)
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- Calculations using dates (4)
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- Aggregation and grouping (8)
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- Creating tables (5)
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- Table-valued functions (6)
- Derived tables and CTEs (13)
- Dynamic SQL (4)
- Pivots (2)
- Triggers (2)
- Archived (70)
SQL | Aggregation and grouping exercise | Show the number of episodes written by each author
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If you haven't already done so, run the script in the above folder to generate the Doctor Who database.
The following diagram shows how the authors and episodes tables are related:
You're probably familiar with this by now!
Use this to show for each author:
- the number of episodes they wrote;
- their earliest episode date; and
- their latest episode date.
If you sort these so that the most prolific authors come first, here are the first few of the 25 rows you should see:
Those who know their Doctor Who won't be surprised at the two leaders.
Save this query as Blink was the best, then close it down.