SQL | LeetCode 1667. 이름 포맷 통일하기 (CONCAT, UPPER, LOWER)

Table: Users

+----------------+---------+
| Column Name    | Type    |
+----------------+---------+
| user_id        | int     |
| name           | varchar |
+----------------+---------+
user_id is the primary key (column with unique values) for this table.
This table contains the ID and the name of the user. The name consists of only lowercase and uppercase characters.

 

Write a solution to fix the names so that only the first character is uppercase and the rest are lowercase.

Return the result table ordered by user_id.

The result format is in the following example.

 

Example 1:

Input: 
Users table:
+---------+-------+
| user_id | name  |
+---------+-------+
| 1       | aLice |
| 2       | bOB   |
+---------+-------+
Output: 
+---------+-------+
| user_id | name  |
+---------+-------+
| 1       | Alice |
| 2       | Bob   |
+---------+-------+

이 문제는 사용자 이름의 형식을 첫 글자는 대문자, 나머지는 소문자로 수정하는 SQL 문제입니다. 

select 
    user_id, 
    concat(upper(substring(name, 1, 1)), 
    lower(substring(name, 2, LENGTH(name)))) as name 
from users 
order by user_id