Question

Lets suppose i have the next tables

Table names
id | name
1  | mike
2  | john
3  | jack

Table attributes
name_id | skill
1 | css
1 | html
1 | php
2 | html
2 | java
2 | css
3 | java

I need to get all id and names that have, for example, css and html attributes. I’ve tried using “JOIN” but the number of attributes to search for may be different.

I did not tried anything else yet because i can’t figure out what to try.

Thank you

Answer 1

Try using GROUP BY ... and HAVING COUNT(DISTINCT ...):

SELECT name_id
FROM attributes
WHERE skill IN ('css', 'html')
GROUP BY name_id
HAVING COUNT(DISTINCT skill) = 2

See it working online: sqlfiddle

You can join to also get the names.