Higher Than 75 Marks¶

Higher Than 75 Marks¶

Tags: Easy Basic Seelct

Links: https://www.hackerrank.com/challenges/more-than-75-marks/problem

Query the Name of any student in STUDENTS who scored higher than 75 Marks. Order your output by the last three characters of each name. If two or more students both have names ending in the same last three characters (i.e.: Bobby, Robby, etc.), secondary sort them by ascending ID.

Input Format

The STUDENTS table is described as follows:

The Name column only contains uppercase (A-Z) and lowercase (a-z) letters.

Sample Input

Sample Output

Ashley
Julia
Belvet

Explanation

Only Ashley, Julia, and Belvet have Marks > . If you look at the last three characters of each of their names, there are no duplicates and 'ley' < 'lia' < 'vet'.

解法一：使用right函数

Name: 'RIGHT'                                                       
Description:                                                        
Syntax:                                                             
RIGHT(str,len)                                                      

Returns the rightmost len characters from the string str, or NULL if
any argument is NULL.                                               

URL: https://dev.mysql.com/doc/refman/5.7/en/string-functions.html  

Examples:                                                           
mysql> SELECT RIGHT('foobarbar', 4);                                
        -> 'rbar'

SELECT name
FROM students
WHERE marks > 75
ORDER BY RIGHT(name, 3), id;

解法二：使用substr函数

Name: 'SUBSTR'
Description:
Syntax:
SUBSTR(str,pos), SUBSTR(str FROM pos), SUBSTR(str,pos,len), SUBSTR(str
FROM pos FOR len)

SUBSTR() is a synonym for SUBSTRING().
//注意下标从1开始计数

SELECT name
FROM students
WHERE marks > 75
ORDER BY SUBSTR(name, length(name) - 2, 3), ID;