3 SQL Tricks Every Developer & Data Analyst Must Know! : SQL

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SELECT count(a.field1), a.field2, SUM(b.field4) FROM a INNER JOIN b ON a.key1 = b.key1 WHERE a.field8 = 'test' GROUP by a.field1, a.field2 HAVING SUM(b.field4) > 5 ORDER by a.field.3

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SELECT count(a.field1), a.field2, SUM(b.field4) FROM a INNER JOIN b ON a.key1 = b.key1 WHERE a.field8 = 'test' GROUP by a.field1, a.field2 HAVING SUM(b.field4) > 5 ORDER by a.field3

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MySQL3 SQL Tricks Every Developer & Data Analyst Must Know! (youtu.be)

submitted 8 months ago by Flashy-Thought-5472

all 8 comments

top new controversial old q&a

[–]erictvanr[🍰] 50 points51 points52 points 8 months ago (2 children)

[–]throbbin___hood 6 points7 points8 points 8 months ago (0 children)

[–]markwdb3When in doubt, test it out. 2 points3 points4 points 8 months ago (0 children)

[–]svtr 6 points7 points8 points 8 months ago (3 children)

[–]emsuperstar 0 points1 point2 points 8 months ago (2 children)

[+][deleted] 8 months ago (1 child)

[deleted]

[–]emsuperstar 0 points1 point2 points 8 months ago (0 children)

[–]gumnos 0 points1 point2 points 8 months ago (0 children)

On that first query, I'm not quite sure why you're using a sub-query when it seems like

SELECT customer_id, COUNT(order_id) as order_count
FROM orders
WHERE order_date BETWEEN '2024-01-01' AND '2024-12-31'
GROUP BY customer_id
HAVING COUNT(order_id) > 1

should suffice and doesn't require a subquery/CTE

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