如何在mysql中通过小写字母获取首字母等数据？

Question

New to mysql,

I have a table like this.

___|____
Id           |    name
1            |       a
2            |       b
3            |       c
4            |       A
5            |       B
6            |       C

---

What will be the query to get the result like this in sql

___|____
Id           |    name
4            |       A
1            |       a
5            |       B
2            |       b
6            |       C
3            |       c

Answer 1

Editted

This seams to be the most easy way changed DDS idea into a more general working one for all MySQL versions..

Query

SELECT 
   id
 , name
FROM 
 Table1
ORDER BY 
  CASE
    WHEN name COLLATE latin1_bin BETWEEN 'A' AND 'Z'
    THEN ASCII(name) + 31
    ELSE ASCII(name)
   END

Result

| id  | name |
| --- | ---- |
| 4   | A    |
| 1   | a    |
| 5   | B    |
| 2   | b    |
| 6   | C    |
| 3   | c    |

View on DB Fiddle

Explaining View so you can see what happens on DB Fiddle

Or the more stabile one because of the unique generated values for the calculated_ascii_value column. Explaining View so you can see what happens on DB Fiddle

The other query is pretty complex..

Query

SELECT 
    Table1.id
  , Table1.name 
FROM (

SELECT 
 DISTINCT
   (
     SUBSTRING_INDEX(SUBSTRING_INDEX(@orderList, ',', number_generator.number), ',', -1)
     COLLATE utf8mb4_bin
   ) AS letter
FROM (

SELECT
 (@number := @number + 1) AS number
FROM (
 SELECT 1 AS number UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9 UNION SELECT 10
) AS row_1
CROSS JOIN (
 SELECT 1 AS number UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6
) AS row_2
CROSS JOIN (SELECT @number := 0) AS init_user_param 

) AS number_generator
CROSS JOIN (SELECT @orderList := 'A,a,B,b,C,c' /* add all to Z,z */) AS init_user_param

) AS letters
INNER JOIN
 Table1
ON
 letters.letter = Table1.name
;

Results

| id  | name |
| --- | ---- |
| 4   | A    |
| 1   | a    |
| 5   | B    |
| 2   | b    |
| 6   | C    |
| 3   | c    |

View on DB Fiddle

Note there are some things you should know

COLLATE utf8mb4_bin might be changed to COLLATE utf8_bin instead when your MySQL uses utf8 charset.

And SELECT @orderList := 'A,a,B,b,C,c' /* add all to Z,z */ you need to might add more to Z,z

Answer 2

this will make a new column 'newid' with the order you need

select newid = row_number() over (order by case when val between 'A' and 'Z' 
                                          then  ascii(val) -31 
                                          else ascii(val) end), *

from yourtable

Answer 3

Try like this. I Just used database from w3schools, need to check if works in MySql.

SELECT * FROM myTable GROUP BY name ORDER BY UPPER(name), LOWER(name);