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Intermediate
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Distinct
Some SQL queries may produce duplicate results. In such cases, duplicate rows may be filtered out using the "DISTINCT" keyword in a static query. In a dynamic query, use the distinct() method.
// Force filtering of duplicate records in the result set.
$query->distinct()Note that DISTINCT can introduce a performance penalty, so do not use it unless there is no other way to restrict the result set to avoid duplicates.
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