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Q- What is the difference between the WHERE and HAVING clauses?

Ans- When GROUP BY is not used, the WHERE and HAVING clauses are essentially equivalent.
However, when GROUP BYis used:
  • The WHERE clause is used to filter records from a result. The filtering occurs before any groupings are made.
  • The HAVING clause is used to filter values from a group (i.e., to check conditions after aggregation into groups has been performed).

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