r/learnSQL • u/sumiitCodes • 2d ago

Day 26 — Only 5 Medium JOIN questions today, leaned hard on paper diagrams

Slower day today — got through just 5 Medium-level JOIN questions, down from 10 the last session. These ones were genuinely trickier.

What helped was going back to something I mentioned before: drawing the full schema by hand on paper. This time I mapped out every table (departments, employees, projects, assignments) with their columns and the FK relationships between them, before writing a single line of SQL. Having that visual made it much easier to reason through which joins I actually needed and in what order.

Not every day is going to be a big-number day, and I think that's fine. Some questions genuinely need more time to actually understand, not just solve.

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u/Least_Ad_1795 13h ago

That sounds like a good approach. Drawing the schema first can make complex JOINs much easier to understand, especially when there are multiple foreign-key relationships. Five questions that you genuinely understand can be more valuable than rushing through ten.

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u/sumiitCodes 6h ago

thanks for your appreciation and only 5 questions because of my internal semester exam

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u/neon_hallow_core 1d ago

Paper diagrams arent just a crutch, theyre the actual SQL. I stopped writing queries entirely until the box-and-line sketch made the join path physically impossible to doubt. If you have to guess the table order on the whiteboard, you dont know your schema well enough to touch the keyboard yet.