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9.13.1. CASE
9.13.2. COALESCE
9.13.3. NULLIF
9.13.4. GREATEST and LEAST

9.14. ��ؿ��ȱ黻��

9.15. ��ؿ�

9.16. ��䤤��碌��

9.16.1. EXISTS
9.16.2. IN
9.16.3. NOT IN
9.16.4. ANY/SOME
9.16.5. ALL
9.16.6. �Ԥ˴ؤ��Ƥ��

9.17. �Ԥ��

9.17.1. IN
9.17.2. NOT IN
9.17.3. ANY/SOME (array)
9.17.4. ALL��
9.17.5. �Ԥ˴ؤ��Ƥ��

9.18. ��֤��ؿ�

9.19. ��ƥ��ؿ�

9.20. ��ƥ��ؿ�

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9.1. ��黻��

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AND

OR

NOT

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`a`	`b`	`a` AND `b`	`a` OR `b`
TRUE	TRUE	TRUE	TRUE
TRUE	FALSE	FALSE	TRUE
TRUE	NULL	NULL	TRUE
FALSE	FALSE	FALSE	FALSE
FALSE	NULL	FALSE	NULL
NULL	NULL	NULL	NULL

`a`	NOT `a`
TRUE	FALSE
FALSE	TRUE
NULL	NULL

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9.1. �����黻��

9.1. ��黻��