Complex MySQL query for specific problemm - mysql

Question

I have searched and gone through the available topics similar to mine. But, failed to find that satisfies my requirements. Hence, posting it here.
I have four tables as follows:
"Organization" table:
--------------------------------
| org_id | org_name |
| 1 | A |
| 2 | B |
| 3 | C |
"Members" table:
----------------------------------------------
| mem_id | mem_name | org_id |
| 1 | mem1 | 1 |
| 2 | mem2 | 1 |
| 3 | mem3 | 2 |
| 4 | mem4 | 3 |
"Resource" table:
--------------------------------
| res_id | res_name | res_prop |
| 1 | resource1 | prop-1 |
| 2 | resource2 | prop-2 |
| 3 | resource3 | prop-3 |
| 4 | resource4 | prop-4 |
| 5 | resource1 | prop-5 |
| 6 | resource2 | prop-6 |
A constraint of UNIQUE INDEX (res_name, res_prop) is applied in the above table.
"member-resource" table:
--------------------------------------------
| sl_no | mem_id | res_id |
| 1 | 1 | 1 |
| 2 | 1 | 2 |
| 3 | 2 | 1 |
| 4 | 4 | 3 |
| 5 | 3 | 4 |
| 6 | 2 | 3 |
| 7 | 4 | 3 |
| 8 | 1 | 5 |
| 9 | 1 | 6 |
I want to find out the distinct res_name from Resource table that have more than one res_prop for a specific organization. For example, expected output for organization A would be as follows:
| res_name | res_prop_count |
| resource1 | 2 |
| resource2 | 2 |
Any help in this regard will highly be appreciated.
Regards.

Answer 1

When doing things like this you should build your query up logically, so to start get all your resources and props from organisation A
SELECT r.res_name,
r.res_prop
FROM Resource r
INNER JOIN `member-resource` mr
ON mr.res_id = r.res_id
INNER JOIN Members m
ON m.mem_id = mr.mem_id
INNER JOIN Organization o
ON o.org_id = m.org_id
WHERE o.org_name = 'A'
Then you can start thinking about how you want to filter it, so you want to find resource names that have more than one different res_prop, so you need to group by res_name, and apply a HAVING clause to limit it to res_names with more than one distinct res_prop:
SELECT r.res_name,
COUNT(DISTINCT r.res_prop) AS res_prop_count
FROM Resource r
INNER JOIN `member-resource` mr
ON mr.res_id = r.res_id
INNER JOIN Members m
ON m.mem_id = mr.mem_id
INNER JOIN Organization o
ON o.org_id = m.org_id
WHERE o.org_name = 'A'
GROUP BY r.res_name
HAVING COUNT(DISTINCT r.res_prop) > 1;
Example on SQL Fiddle

Answer 2

I'm not entirely sure I understand what you are looking for, but I think this should work:
SELECT Resource.res_name,
COUNT(DISTINCT Resource.res_prop) AS res_prop_count
FROM Resource
INNER JOIN member_resource
USING (res_id)
INNER JOIN Members
USING (mem_id)
INNER JOIN Organization
USING (org_id)
WHERE Organization.org_name = 'A'
GROUP BY res_name
HAVING res_prop_count > 1;

Answer 3

try this:
select
res_name, count(res_prop) as res_prop_count
from
Resource
where
res_id in (select
res_id
from
member_resource
where
mem_id in (select
mem_id
from
Members
where
org_id = (select
org_id
from
Organization
where
org_name = 'A'))) group by res_name

Answer 4

Try this:
If you have Organization ID then use the query below:
SELECT r.res_name, COUNT(DISTINCT r.res_prop) res_prop_count
FROM member-resource mr
INNER JOIN Resource r ON mr.res_id = r.res_id
INNER JOIN Members m ON mr.mem_id = r.mem_id
WHERE m.org_id = 1
GROUP BY r.res_id HAVING res_prop_count > 1;
If you have Organization name then use the query below:
SELECT r.res_name, COUNT(DISTINCT r.res_prop) res_prop_count
FROM member-resource mr
INNER JOIN Resource r ON mr.res_id = r.res_id
INNER JOIN Members m ON mr.mem_id = r.mem_id
INNER JOIN Organization o ON m.org_id = o.org_id
WHERE m.org_name = 'A'
GROUP BY r.res_id HAVING res_prop_count > 1