你可以用 SUBSTRING() 取回…的一部分 VARCHAR 类型。例如：

select
  substring(phone_number, 3, 3) as phone_area_code
  substring(phone_number, 6, 7) as phone_number
from t

您可以使用左右函数来获得区号和电话号码

select LEFT(REPLACE(phone_number,'+1',''),3) AS phone_area_code,
       RIGHT(phone_number,7) AS phone_number
from 
(
values
(NULL    ,'+11234567890'),
(NULL    ,'+11234567890'),
(NULL    ,'+11234567890'),
(NULL    ,'+11234567890')
) as cte_phone(phone_area_code,phone_number)

+-----------------+--------------+
| phone_area_code | phone_number |
+-----------------+--------------+
|             123 |      4567890 |
|             123 |      4567890 |
|             123 |      4567890 |
|             123 |      4567890 |
+-----------------+--------------+