mysql：选择*其中名字和姓氏以相同的字母开头

-这将选择名字和姓氏相同的人，但这仅适用于

m

。如何从a到z选择所有此类人员（按desc排序不是问题）

说明：取名字和姓氏最左边的1个字符，将其转换为大写，并进行比较

SELECT * FROM `people` WHERE first_name like 'm%' and last_name like 'm%';

select *
 from people
 where substring(first_name,1,1) = substring(last_name,1,1)
 order by last_name, first_name

SELECT * FROM people WHERE LEFT(first_name, 1) = LEFT(last_name, 1);
ORDER BY last_name, first_name

SELECT * FROM `people` WHERE UPPER(LEFT(first_name, 1)) = UPPER(LEFT(last_name, 1))