MySQL数据库SUBSTRING_INDEX的运用

一、如何运用SUBSTRING_INDEX截取address的省市区

二、应用SUBSTRING_INDEX函数进行多次嵌套截取

SELECT
  SUBSTRING_INDEX(t1.`address`, '_', '1') AS '国家',
  SUBSTRING_INDEX(
    (
      SUBSTRING_INDEX(t1.`address`, '_', '2')
    ),
    '_',
    - 1
  ) AS '省',
  SUBSTRING_INDEX(
    (
      SUBSTRING_INDEX(t1.`address`, '_', '3')
    ),
    '_',
    - 1
  ) AS '市',
  SUBSTRING_INDEX(t1.`address`, '_', '-1') AS '区'
FROM
  user1 t1;