oracle中判断某个字段是不是存在

oracle中判断某个字段是否存在

oracle中判断某个字段是否存在

select name,sum(decode(subject,'语文', grade,null)) "语文", sum(decode(subject,'数学', grade,null)) "数学", sum(decode(subject,'英语', grade,null)) "英语" from student group by name

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