下面应该给你方向
SELECt * FROM(SELECt * FROM <somewhere w/o my_field>),(SELECt * FROM <somewhere with my_field>)
假设原始表（）中有a，b和c作为字段-如果您需要将缺失值从NULL更改为0，则可以使用上面的内容（见下文）：
SELECt a, b, c, COALESCE(my_field, 0) as my_fieldFROM(SELECt * FROM <somewhere w/o my_field>),(SELECt * FROM <somewhere with my_field>)
