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REComment SQL and I’ll send you the link to my book Mastering SQL Window Functions.
I used to compare sales using messy self-joins.
Slow. Confusing. Hard to explain.
Then I learned LAG() and LEAD().
No joins. Cleaner SQL. Better performance.
If you’re into SQL or a data analyst looking to optimize queries—this one’s for you.
#sql #dataanalyst
@rebellionrider










