Be honest — how many times have you Googled "SQL find duplicate rows" this year? Some queries just...
Be honest — how many times have you Googled "SQL find duplicate rows" this year? Some queries just never stick in my head. Here are 5 I re-look-up constantly, with working answers you can copy. Syntax is PostgreSQL, with notes where other databases differ.
1. Find duplicate rows
SELECT email, COUNT(*) AS count
FROM users
GROUP BY email
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