sql / expert
Snippet
Universal Quantification with the ALL Predicate
The ALL predicate compares a scalar value against every value in a subquery's result set. It returns true only if the comparison holds for every row, providing a concise way to implement universal quantification logic.
snippet.sql
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SELECT project_idFROM projectsWHERE budget > ALL (SELECT avg_costFROM regional_benchmarks);
Breakdown
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WHERE budget > ALL (...)
The predicate ensures the budget is strictly greater than every single value returned by the subquery.
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SELECT avg_cost FROM regional_benchmarks
A subquery generating the set of values for the universal comparison.