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1. EXISTS ×ÓÅÌÎÊ

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SELECT * FROM table1
WHERE EXISTS (SELECT 1 FROM table2 WHERE table2.column = table1.column);

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2. CASE ±í´ïʽ

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SELECT CASE
  WHEN table1.column IN ('value1', 'value2') THEN 'match'
  ELSE 'no match'
END AS result
FROM table1;

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3. OR ÔËËã·û

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WHERE table1.column = 'value1' OR table1.column = 'value2';

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