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Difference between WHERE and HAVING



1> WHERE Clause
  • Filters rows before grouping.
  • Works with non-aggregate conditions (like simple comparisons on columns).
Eg : SELECT employee, bonus FROM emp_bonus WHERE bonus > 5000;

2> HAVING Clause

  • Filters groups after aggregation.

  • Works with aggregate functions (SUM, AVG, MAX, MIN, COUNT).

Eg : SELECT employee, SUM(bonus) FROM emp_bonus GROUP BY employee HAVING SUM(bonus) > 5000;

💡 In Short : 

  1. WHERE = "Which rows should I include in the group?"

  2. HAVING = "Which groups should I keep after aggregation?"

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