Below I have an MySQL database where "id" is just an id for each row. "question" shows the id of the question. There are four questions, 11, 12, 13 and 14. For every question the user has four answer options (1,2,3 and 4) which is stored in the "answer" column. The "user" column indicates what user who answered. In this example we have user 10, 11 and 12
id question answer user
1 11 2 10
2 12 2 10
3 13 3 10
4 14 4 10
5 11 2 11
6 12 2 11
7 13 4 11
8 14 1 11
9 11 2 12
10 12 2 12
11 13 1 12
12 14 1 12
Let's say that user 10 is the reference user which means that I want to know how well user 10 matches with the others. Using SQL and/or php code how can I match the answers of the users such that I get the matches in percent with the highest percent shown first. So in this example I'm looking for something like.
user percent
1 11 50%
2 12 75%
I'm not sure if this is possible all the way with only SQL. Maybe a bit of php is needed to convert the count to % for instance.
Finally i got your desired output
Try this:
SELECT * ,round(count(*)/(SELECT count(*) FROM `list` where user=10)*100) as
pecentage FROM `list` as l where l.answer=(SELECT m.answer FROM `list` as m
where m.user=10 and l.question=m.question) group by (l.user) order by pecentage
It will produce out put as
and you can add l.user!=10 in where condition if you don't want user 10 value.
Related
As first please be nice to me im a beginner with SQL language and english language.
So i have problem with this query.
I've created sqlfiddle.
My query look like it's working properly but I find it is not working
I would like to write a query that returns the product ID variant based on the parameters that will send
Correct query result would look like the following
PARAM = 6
id product_id productvariant_id attributevalue_id
1 3 1 6
2 3 2 6
---- BAD RESULTS -----
3 3 3 6
4 3 3 9
6 3 5 6
7 3 6 6
8 3 6 11
PARAM = 6,9
id product_id productvariant_id attributevalue_id
3 3 3 6
4 3 3 9
---- BAD RESULTS -----
3 3 3 6
4 3 3 9
6 3 5 6
7 3 6 6
8 3 6 11
What i really need is return productvariant_id which contains combination of inserted params, if I send only one attributevalue_id, i need to find productvariant which contain only ONE attributevalue_id. IF i send two params i finding combination of two.. not more or less
Unfortunately I do not have enough reputation for a comment, thus I have to write this as answer.
Could you clarify your goal?
Do you want to retrieve the productvariant_id of all datasets where the attributevalue_id matches your parameter?
SELECT productvariant_id
FROM productvariantattribute
WHERE attributevalue_id IN ($YOUR_PARAMETER_LIST);
Or do you want to retrieve the productvariant_id of all datasets where the productvariant_id has only these attributevalue_ids you specified as parameter?
SELECT `productvariant_id`
FROM `productvariantattribute`
WHERE `attributevalue_id` IN ($YOUR_PARAMETER_LIST)
AND `productvariant_id` NOT IN (
SELECT `productvariant_id`
FROM `productvariantattribute`
WHERE `attributevalue_id` NOT IN ($YOUR_PARAMETER_LIST)
)
I'm having trouble making a solution with this problem: my database looks like this.
ID parent_cat_id child_cat_id
1 27 10
2 15 20
3 80 90
4 90 88
5 60 30
6 88 40
7 15 60
8 30 40
9 27 95
10 40 30
The context is the user selects a category for product search, I need to get that category IDs and all of it's children which can go 4 levels deep.
The database is similar to this post:
Check if column value exists in another column in SQL
However the OP only needs 1 match for me it needs to be recursive. I'm still trying out several solutions but I'm at a loss. Would love some suggestions.
Thanks in advance.
I've got a table with 3 separate scores in 3 separate fields:
User / Score 1 / Score 2 / Score 3
Person 1: 10 21 7
Person 2: 17 4 20
Person 3: 1 5 22
Is there a mysql command that will effectively sort each person out by the highest score from the 3 fields.
So here I need it to return:
Person 3: 1 5 22
Person 1: 10 21 8
Person 2: 17 4 20
The only way I can think of doing it would be to put them in an array, check each number for each person against each other to find the highest, then sort them into a different array.
This seems very long-winded and labour intensive though.
Add order by greatest(score1,score2,score3) desc
Manual for GREATEST()
This question already has answers here:
Select most common value from a field in MySQL
(3 answers)
Closed 8 years ago.
I don't know how to phrase this, but I'm trying to get the rows with the most occurrences in the column to display, for example
ID from_id to_id
1 1 3
2 1 3
3 1 3
4 1 3
5 2 3
6 3 3
7 3 3
8 4 3
9 4 3
I'm trying to get 1,4,3 from the database because it's more frequent, how would I do this?
Sorry if it's a bad question, I don't know how to phrase it
This is quite easy, just COUNT(from_id), eg like this
SELECT from_id, COUNT(from_id) AS total FROM your_table
GROUP BY from_id
ORDER BY total DESC
You can now modify this, eg LIMIT 10 to get the top 10 or WHERE total > 1 before the GROUP BY to only get rows which occure more than once.
I've done some digging and I can't find an effective way to prevent duplicate entries based on my needs. I need columns 2 (proj_id) and column 4 (dept_id) never to be the same, as each dept would only work on a project once. So, rows 1 and 4, 6 and 7, and 14 and 15 shouldn't be allowed. I'll keep digging as well.
summary_id proj_id hours_id dept_id date_entered
1 8 3 6 9/9/2012
2 2 2 6 9/9/2012
3 1 6 19 9/9/2012
4 8 3 6 9/9/2012
5 2 5 17 9/9/2012
6 7 2 5 9/9/2012
7 7 2 5 9/9/2012
8 2 5 17 9/9/2012
9 7 4 17 10/10/2012
10 3 6 1 10/10/2012
11 5 1 15 10/10/2012
12 4 4 3 10/10/2012
13 3 5 1 10/10/2012
14 8 2 13 10/10/2012
15 8 2 13 10/10/2012
Before applying unique combine key to your table, you have to remove duplicate records first then apply the following sql command:
ALTER TABLE your_table_name ADD UNIQUE (proj_id, dept_id);
Define an unique key on both columns
ALTER TABLE `your_table` ADD UNIQUE (`proj_id`, `dept_id`);
Looks like you are new to php and mysql. So here's the easiest way to do it.
Log on to PHPMyAdmin
Select your DB and your table.
View the Structure of it (clicking the button on top of the screen).
Check the two fields (proj_id and dept_id) using the check box on the left.
At the bottom of the table you should find the the words "With selected" and in front of it some actions. Select the option to make "Primary".
Of course, if you have duplicate entries first delete them.