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²»Äܵ¥¶ÀʹÓ㺠Must be preceded by =, !=, >, <, <=, >=.
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SOME (ANY)
Evaluates to FALSE if the query returns no rows.
ALL
Evaluates to TRUE if the query returns no rows.
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SQL> select max(salary) from employees;
 
MAX(SALARY)
-----------
      24000
 
SQL> select min(salary) from employees;
 
MIN(SALARY)
-----------
       2100
 
SQL> select count(1) from employees;
 
  COUNT(1)
----------
       107
 
SQL>
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SQL> SELECT count(1) from employees WHERE salary >= any (select 1 from dual where 1 < 1);
 
  COUNT(1)
----------
         0
 
SQL> SELECT count(1) from employees WHERE salary >= some (select 1 from dual where 1 < 1);
 
  COUNT(1)
----------
         0
 
SQL> SELECT count(1) from employees WHERE salary <= ALL (select 1 from dual where 1 < 1);
 
  COUNT(1)
----------
       107
 
SQL>


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