MySQL字符串处理

CONCAT函数

SELECT column_name1,CONCAT(column_name2,str,column_name3),column_name4 FROM table_name;

SELECT
  id,
  concat(hero_name, '的胜率是', win_rate)
FROM
  timi_adc;

如果拼接 的值中含有NULL ，则结果一律为NULL

SELECT
  concat(hero_name, '的胜率是', win_rate)
FROM
  timi_adc
WHERE
  id = 3;

别名

SELECT
  concat(hero_name, '的胜率是', win_rate) as result
FROM
  timi_adc
WHERE
  id = 3;

SELECT
  concat(hero_name, '是T0英雄，他的的胜率是', win_rate,',出场率是',appearance_rate,',ban率是',ban_rate)
FROM
  timi_adc
where 
fever = 'T0';

TRIM函数

去除空格

TRIM (str)

SELECT
  trim(hero_name),
  trim(fever)
FROM
  timi_adc
WHERE
  id = 20;

语法拓展

TRIM( BOTH|LEADING|TRAILING removed_str FROM str);

REPLACE（）函数

REPLACE（）修改字符串，但是可以直接用UPDATE语句。

UPDATE table_name 
SET colunm_name = 
REPLACE(column_name,string_find,string_to_replace) 
WHERE conditions;

去掉结果中左边空格，并取个别名name

SELECT
  TRIM(
    LEADING 
    FROM
      hero_name
  )
AS 
name

SELECT
  TRIM(
    TRAILING 'T1Q'
    FROM
      fever
  ) as result
FROM
  timi_adc
WHERE
  hero_name like "%后%"
  and hero_name not in ("后羿");