Pgsql特殊排序

对字段值为A，B，C，D的时候进行特殊排序。

CASE
        WHEN aa = 'H' THEN
            '0'
        WHENaa = 'O' THEN
            '1'
        ELSE
            aa
        END

对数字进行排序，升序，0排到最后面

        CASE
        WHEN bb = 0 THEN
            999999999999
        ELSE
            bb
        END

 自定义排序

 ORDER BY FIELD(Biz_ExamQuestion.questionType,"3","1","2","4","5")