SQL查询以特定条件分组

Question

My table data:

id      fieldId  Name   Text
----    ------  -----   ----
1        101    name1   a1
2        102    name2   a2
3        101    name1   a1
4        103    name3   a2
5        102    name2   a3
6        101    name1   c1
7        101    name1   a3
8        102    name2   
9        101    name1   b2
10       103    name3   c1

I need output like

Name    Count(fieldId)  Count_id_text_is_either_a1_or_a2_a3
------      ------        -------
name1   4                   2
name2   3                   2
name3   2                   1

• Name = I need to group by fieldId.
• Count(fieldId) = Count each group records.
• Count_id_text_is_either_a1_or_a2_a3 = This is the column I want the count of records of group only if Text like 'a1-%' or 'a2-%' or 'a3-%' .

Can this be done by single query? If yes the please explain how? If no then what is the most efficient way to do this?

Answer 1

select Name, 
    count(*) as CountAll, 
    count(case when Text like 'a1-%' or Text like 'a2-%' or Text like 'a3-%' then 1 end) as CountA1A2A3
from MyTable
group by Name

You could also use a RegEx if you wish.

Answer 2

Here.

SELECT
    `Name`,
    COUNT(*) AS 'fieldId',
    COUNT(IF(`Text` REGEXP '^a[1-3]',1,NULL)) AS 'a1a2a3'
FROM (SELECT * FROM `items` GROUP BY `Name`,`Text`) t1
GROUP BY `Name`;