Aggregate rows by id comparing column values - mysql

Question

I have the following table that groups users by their permissions
userIds permissions
4,5,7,8 100,1600,500,501,502,400,401,1500,1501
The numbers in the permissions column are the sections ids.
Some of these sections may have other data associated which I retrieved and stored in another table.
sectionId userId resourceId
100 4 NULL
1600 4 NULL
500 4 NULL
501 4 NULL
502 4 NULL
400 4 NULL
401 4 1
1500 4 NULL
1501 4 NULL
100 5 NULL
1600 5 NULL
500 5 NULL
501 5 NULL
502 5 NULL
400 5 NULL
401 5 1,2
1500 5 NULL
1501 5 NULL
100 7 NULL
1600 7 NULL
500 7 NULL
501 7 NULL
502 7 NULL
400 7 NULL
401 7 2
1500 7 NULL
1501 7 NULL
100 8 NULL
1600 8 NULL
500 8 NULL
501 8 NULL
502 8 NULL
400 8 NULL
401 8 1
1500 8 NULL
1501 8 NULL
My goal is to compare, for each user in the userIds column of the first table (splitted by comma), every row of the second table in order to check if each user has the same resourceId value for that specific sectionId.
If one or more users have the same resourceId value for each section I want to keep them group together, otherwise they need to be on different rows.
This is the output I'm expecting from the sample data provided:
userIds permissions
4,8 100,1600,500,501,502,400,401,1500,1501
5 100,1600,500,501,502,400,401,1500,1501
7 100,1600,500,501,502,400,401,1500,1501
UPDATE
I managed to get the desidered output in the following way:
-- Numbers table creation
DROP temporary TABLE IF EXISTS tally;
CREATE temporary TABLE tally
(
n INT NOT NULL auto_increment PRIMARY KEY
);
INSERT INTO tally
(n)
SELECT NULL
FROM (SELECT 0 AS N
UNION ALL
SELECT 1
UNION ALL
SELECT 2
UNION ALL
SELECT 3
UNION ALL
SELECT 4
UNION ALL
SELECT 5
UNION ALL
SELECT 6
UNION ALL
SELECT 7
UNION ALL
SELECT 8
UNION ALL
SELECT 9) a,
(SELECT 0 AS N
UNION ALL
SELECT 1
UNION ALL
SELECT 2
UNION ALL
SELECT 3
UNION ALL
SELECT 4
UNION ALL
SELECT 5
UNION ALL
SELECT 6
UNION ALL
SELECT 7
UNION ALL
SELECT 8
UNION ALL
SELECT 9) b;
-- Split users by comma from first table
DROP temporary TABLE IF EXISTS tmppermissions2;
CREATE temporary TABLE tmppermissions2
(
userid VARCHAR(255) NOT NULL,
permissions TEXT NOT NULL
);
INSERT INTO tmppermissions2
SELECT userid,
permissions
FROM (SELECT Substring_index(Substring_index(t.userids, ',', tally.n), ',', -1
)
userId,
t.permissions
permissions
FROM tally
INNER JOIN tmppermissions t
ON Char_length(t.userids) - Char_length(
REPLACE(t.userids, ',',
'')) >=
tally.n - 1
ORDER BY n) AS split;
-- Gets the users with the same permissions
DROP temporary TABLE IF EXISTS sharedprofiles;
CREATE temporary TABLE sharedprofiles
(
userids VARCHAR(255) NOT NULL,
permissions TEXT NOT NULL,
profileid INT(11)
);
INSERT INTO sharedprofiles
SELECT Group_concat(userid),
permissions,
NULL
FROM tmppermissions2
WHERE userid NOT IN (SELECT split.userid
FROM (SELECT Substring_index(Substring_index(r.userids,
',',
t.n), ',', -1)
userId
FROM tally t
INNER JOIN tmppermissions r
ON Char_length(r.userids)
- Char_length(
REPLACE(r.userids, ',',
'')) >=
t.n - 1
WHERE Position(',' IN r.userids) > 0
ORDER BY n) AS split
WHERE split.userid IN (SELECT *
FROM (SELECT Group_concat(userid
ORDER
BY userid ASC)
AS
users
FROM
tmpcurrentresources2
GROUP BY resourceid,
sectionid
ORDER BY users) b
WHERE Position(',' IN b.users) =
0))
GROUP BY permissions
ORDER BY Group_concat(userid);
-- Gets the users with specific permissions
DROP temporary TABLE IF EXISTS singleprofiles;
CREATE temporary TABLE singleprofiles
(
userid VARCHAR(255) NOT NULL,
permissions TEXT NOT NULL,
profileid INT(11)
);
INSERT INTO singleprofiles
SELECT userid,
permissions,
NULL
FROM tmppermissions2
WHERE userid IN (SELECT split.userid
FROM (SELECT Substring_index(Substring_index(r.userids, ',',
t.n),
',', -1)
userId
FROM tally t
INNER JOIN tmppermissions r
ON Char_length(r.userids) -
Char_length(
REPLACE(r.userids, ',',
'')) >=
t.n - 1
WHERE Position(',' IN r.userids) > 0
ORDER BY n) AS split
WHERE split.userid IN (SELECT *
FROM (SELECT Group_concat(userid
ORDER BY
userid ASC)
AS
users
FROM tmpcurrentresources2
GROUP BY resourceid,
sectionid
ORDER BY users) b
WHERE Position(',' IN b.users) = 0))
ORDER BY userid;
-- Merge the results
SELECT *
FROM sharedprofiles
UNION
SELECT *
FROM singleprofiles;
I'm wondering if there is a more concise way to accomplish the same result.

Answer 1

The solution (as I suspect you already know) is to normalise your schema.
So instead of...
userIds permissions
4,5 100,1600,500
...you might have
userIds permissions
4 100
4 1600
4 500
5 100
5 1600
5 500