Question

Oracle中的以下case语句给出了一个错误。请帮忙。错误是：ORA：00907。

select * from schools_master_table where  TEST_SUBJECT_KEY in  (case 
when SCHOOL_YEAR<=2014 and TEST_GRADE_KEY in (3,4,5,6,7,8,10) THEN (1,2,3,4,5)
when SCHOOL_YEAR >2014 and TEST_GRADE_KEY in (10) THEN (1,3)
when SCHOOL_YEAR>2014 and TEST_GRADE_KEY in (3,4,5,6,7,8) THEN (1,2,3,4,5)
when SCHOOL_YEAR>2014 and TEST_TYPE_KEY in (11) THEN  (17,18,19,20,21,22,23,24,25)
ELSE NULL 
END)

Answer 1

case expression syntax允许返回表达式和else表达式。这里重要的是需要an expression，“......评估值”。您尝试返回an expression list，而这在案例构造中无效。您可以通过一个简单的示例看到：

select case when 1=1 then (1,2) end from dual;

也得到ORA-00907:missing right parenthesis并且错误被标记为逗号所在的位置 - 因为它期望看到围绕单个表达式而不是列表的集合中的右括号。

您可以使用OR和AND的组合，在其他条件匹配时，根据相应的列表检查TEST_KEY_SUBJECT值：

select * from schools_master_table
where (SCHOOL_YEAR<=2014 and TEST_GRADE_KEY in (3,4,5,6,7,8,10)
  and  TEST_SUBJECT_KEY in (1,2,3,4,5))
or (SCHOOL_YEAR>2014 and TEST_GRADE_KEY in (10)
  and TEST_SUBJECT_KEY in (1,3))
or (SCHOOL_YEAR>2014 and TEST_GRADE_KEY in (3,4,5,6,7,8)
  and TEST_SUBJECT_KEY in (1,2,3,4,5))
or (SCHOOL_YEAR>2014 and TEST_TYPE_KEY in (11)
  and TEST_SUBJECT_KEY in (17,18,19,20,21,22,23,24,25))

在我写一个案例陈述时得到错误ORA：00907

1 个答案: