Let's say i have a simple table voting with columns
id(primaryKey),token(int),candidate(int),rank(int).
I want to extract all rows having specific rank,grouped by candidate and most importantly only with minimum count(*).
So far i have reached
SELECT candidate, count( * ) AS count
FROM voting
WHERE rank =1
AND candidate <200
GROUP BY candidate
HAVING count = min( count )
But,it is returning empty set.If i replace min(count) with actual minimum value it works properly.
I have also tried
SELECT candidate,min(count)
FROM (SELECT candidate,count(*) AS count
FROM voting
where rank = 1
AND candidate < 200
group by candidate
order by count(*)
) AS temp
But this resulted in only 1 row,I have 3 rows with same min count but with different candidates.I want all these 3 rows.
Can anyone help me.The no.of rows with same minimum count(*) value will also help.
Sample is quite a big,so i am showing some dummy values
1 $sampleToken1 101 1
2 $sampleToken2 102 1
3 $sampleToken3 103 1
4 $sampleToken4 102 1
Here ,when grouped according to candidate there are 3 rows combining with count( * ) results
candidate count( * )
101 1
103 1
102 2
I want the top 2 rows to be showed i.e with count(*) = 1 or whatever is the minimum
Try to use this script as pattern -
-- find minimum count
SELECT MIN(cnt) INTO #min FROM (SELECT COUNT(*) cnt FROM voting GROUP BY candidate) t;
-- show records with minimum count
SELECT * FROM voting t1
JOIN (SELECT id FROM voting GROUP BY candidate HAVING COUNT(*) = #min) t2
ON t1.candidate = t2.candidate;
Remove your HAVING keyword completely, it is not correctly written.
and add SUB SELECT into the where clause to fit that criteria.
(ie. select cand, count(*) as count from voting where rank = 1 and count = (select ..... )
The HAVING keyword can not use the MIN function in the way you are trying. Replace the MIN function with an absolute value such as HAVING count > 10
Related
I'm a bit stuck cause am not sure if I am looking the wrong way casue I can't find anything related to what I am looking for. So I want to give an example for what I am trying to do. NOTE: not real scenario.
I have a count on a field:
SELECT count(user_id)
FROM usersgroups
group by user_id
Now I want to make a calc with the max value from the count. Something like:
SELECT count(user_id) as count,
SUM(max(count(user_id)) / count(user_id)) as blub
FROM usergroups
group by user_id
But I get error invalid use of group function cause I think I cant use the COUNT() function inside the SUM function?
So is there any other way to make that calculation.
P.S. the calc is for calculating the percentage of the max value to the record/current value.
UPDATE
So what I expect is a percentage like
count | percentage
5 | 1
4 | 0.8
3 | 0.6
2 | 0.3
1 | 0.2
5/5 = 1
4/5 = 0.8
3/5 = 0.6
2/5 = 0.4
1/5 = 0.2
In a separate Derived Table, you can fetch the maximum count value out of all the counts. I have simply used ORDER BY COUNT(user_id) DESC LIMIT 1 to fetch the same.
CROSS JOIN this result-set with the usergroups table, so that every row in the usergroups table has access to the maximum count value.
Now, you can simply use the GROUP BY and appropriate aggregation to determine the "percent".
Note that, for GROUP BY to be valid, SELECT clause must contain either aggregated columns/expressions only, or the columns specified in the GROUP BY clause. That is why MAX() is used over the maximum count value. Since that value is only a scalar, so MAX() will return the same value only.
Try the following:
SELECT
ug.user_id,
COUNT(ug.user_id) AS user_count,
COUNT(ug.user_id) / MAX(mcnt.count) AS percent
FROM
usergroups AS ug
CROSS JOIN
(
SELECT COUNT(user_id) AS count
FROM usersgroups
GROUP BY user_id
ORDER BY COUNT(user_id) DESC LIMIT 1
) AS mcnt
GROUP BY ug.user_id
ORDER BY user_count DESC
Count available user_id as subquery, then divide user_id values by the sum of count.
select user_id/ sum(count) as percentage
from(
select count(user_id) as count , user_id
from usergroups
where user_id != 0
group by user_id
) as A
group by count, user_id
I have a query that returns following values:
TemplateCode Total
1418 35
7419 31
7418 31
8325 17
15623 17
4997 17
I want all the rows with top 3 Total values
In my query if I include LIMIT 3 in the query then it gives only 3 which I don't want. I don't want to include LIMIT because count may vary from time to time.
How can I include condition on Total and always get top 3 count values
My current query is like:
select TemplateCode, count(*) as Total from table group by TemplateCode
order by Total desc
limit 3
I think this does what you want:
select t.*
from t
where t.Total >= (select distinct t2.Total
from t t2
order by t2.Total desc
limit 2, 1
);
This assumes that you want the third distinct value. If you just want the third value, remove the distinct.
You could use a inner join on subquery for the top 3 total
select m.TemplateCode , m.total
from my_table m
inner join (
select Total
from my_table
order by Total Desc
limit 3
) t on t.total = m.total
order by m.total, m.TemplateCode
Have a table with similar schema
id control code amount
1 200 12 300
2 400 12 300
3 200 12 300
4 100 10 400
5 100 10 400
6 500 13 500
Trying to list the duplicates of records on a UI.
Using following query I can retrieve the duplicate records and show it on UI.
select * from mwt group by control,code,amount having count(id) > 1;
id control code amount
1 200 12 300
4 100 10 400
Here the records with id 1 and 4 are duplicates of 3 and 5 respectively.
On the UI, the user will click a check-box adjacent to the record and corresponding duplicate records should be populate to the UI. To make things easier trying to populate another column named dup_id. Using this dup_id it is possible to filter the results from UI , which is in the JSON format.
How to create a result set similar to the one shown below?
id control code amount dup_id
1 200 12 300 1
2 400 12 300
3 200 12 300 1
4 100 10 400 4
5 100 10 400 4
6 500 13 500
This seems like a simpler solution than that suggested by #kickstarter - but maybe I've misunderstood the requirement...
SELECT x.*
, y.dup_id
FROM my_table x
LEFT
JOIN
( SELECT MIN(id) dup_id
, control
, code
, amount
FROM my_table
GROUP
BY control
, code
, amount
HAVING COUNT(*) > 1
) y
ON y.control = x.control
AND y.code = x.code
AND y.amount = x.amount;
Depending on how accurate the order has to be, you could do something like this.
This is getting all the unique control / code / amount with a count, to get a flag to know if that is a duplicate row, and ordered by control / code / amount so that they are in order. It does a cross join to initialise a few user variables.
Then it calculates a counter, only incrementing it if any of control / code / amount have changed AND it is a duplicate row. Then sets user variables to store the previous values of control / code / amount.
The outer query then orders the results back in to id order.
SELECT sub3.id,
sub3.control,
sub3.code,
sub3.amount,
sub3.dup_id
FROM
(
SELECT sub2.id,
sub2.control,
sub2.code,
sub2.amount,
#cnt:=IF(#control=control AND #code=code AND #amount=amount AND sub2.id_count IS NOT NULL, #cnt, IF(sub2.id_count IS NULL, #cnt, #cnt + 1)),
#control:=control,
#code:=code,
#amount:=amount,
IF(sub2.id_count IS NULL, NULL, #cnt) AS dup_id
FROM
(
SELECT mwt.id, mwt.control, mwt.code, mwt.amount, sub1.id_count
FROM mwt
LEFT OUTER JOIN
(
SELECT control, code, amount, COUNT(id) AS id_count
FROM mwt
GROUP BY control,code,amount
HAVING id_count > 1
) sub1
ON mwt.control = sub1.control
AND mwt.code = sub1.code
AND mwt.amount = sub1.amount
ORDER BY mwt.control, mwt.code, mwt.amount
) sub2
CROSS JOIN
(
SELECT #cnt:=0, #control:=0, #code:=0, #amount:=0
) sub0
) sub3
ORDER BY id
Note that this is ordering by control, code and amount, so not an exact match for your required output (which would require getting the first duplicates ordered by id first).
EDIT - Simpler and better way to do it. This gets all the duplicate rows with the min id for those duplicates (ordered by the min id), and uses a user variable to add a sequence number for those. Then LEFT OUTER JOINs that back against the main table to put that sequence number in all the matching rows.
SELECT mwt.id, mwt.control, mwt.code, mwt.amount, sub2.dup_id
FROM mwt
LEFT OUTER JOIN
(
SELECT sub1.id, sub1.control, sub1.code, sub1.amount, #cnt:=#cnt+1 AS dup_id
FROM
(
SELECT MIN(id) AS id, control, code, amount
FROM mwt
GROUP BY control,code,amount
HAVING COUNT(id) > 1
ORDER BY id
) sub1
CROSS JOIN
(
SELECT #cnt:=0
) sub0
) sub2
ON mwt.control = sub2.control
AND mwt.code = sub2.code
AND mwt.amount = sub2.amount
ORDER BY mwt.id
Would you need a dup_id column ?. I hope this can be achieved with a simple query like below
select id
, control
, code
, amount
from table
where control = from selected Record
and code = from selected Record
and amount = from selected Record
and id not equals from selected Record
You can very well omit the last not equals if the requirement is to list down duplicates including the selected record.
I have table that looks like this:
id rank
a 2
a 1
b 4
b 3
c 7
d 1
d 1
e 9
I need to get all the distinct rank values on one column and count of all the unique id's that have reached equal or higher rank than in the first column.
So the result I need would be something like this:
rank count
1 5
2 4
3 3
4 3
7 2
9 1
I've been able to make a table with all the unique id's with their max rank:
SELECT
MAX(rank) AS 'TopRank',
id
FROM myTable
GROUP BY id
I'm also able to get all the distinct rank values and count how many id's have reached exactly that rank:
SELECT
DISTINCT TopRank AS 'rank',
COUNT(id) AS 'count of id'
FROM
(SELECT
MAX(rank) AS 'TopRank',
id
FROM myTable
GROUP BY id) tableDerp
GROUP BY TopRank
ORDER BY TopRank ASC
But I don't know how to get count of id's where the rank is equal OR HIGHER than the rank in column 1. Trying SUM(CASE WHEN TopRank > TopRank THEN 1 END) naturally gives me nothing. So how can I get the count of id's where the TopRank is higher or equal to each distinct rank value? Or am I looking in the wrong way and should try something like running totals instead? I tried to look for similar questions but I think I'm completely on a wrong trail here since I couldn't find any and this seems a pretty simple problem that I'm just overthinking somehow. Any help much appreciated.
One approach is to use a correlated subquery. Just get the list of ranks and then use a correlated subquery to get the count you are looking for:
SELECT r.rank,
(SELECT COUNT(DISTINCT t2.id)
FROM myTable t2
WHERE t2.rank >= r.rank
) as cnt
FROM (SELECT DISTINCT rank FROM myTable) r;
TABLE quotation
id clientid
1 25
2 25
3 25
4 25
5 26
How can I query how many different clients exist in TABLE quotation? I don't want duplicate entries to be counted more than once.
I need the answer to be 2, in 1 row, because the only non-duplicated entries are (25, 26).
select count(distinct clientid) from quotation
read more
I find a way out
SELECT COUNT(*) as total FROM (SELECT COUNT(*) FROM quotation GROUP BY
clientid) t1
If you want to count the total number of unique entries this will return a number in column count.
SELECT COUNT(*) as total FROM (SELECT COUNT(*) FROM quotation GROUP BY clientid having count(*) > 1) t1
If you want to count the total number of entries with duplicate rows then use the following mysql.
SELECT COUNT(*) as total FROM (SELECT COUNT(*) FROM quotation GROUP BY clientid having count(*) >= 2) t1
I tried the following on a MySQL 5.x database.
id is an integer and clientid is an integer. I populated with two rows:
id clientid
1 25
2 25
This SQL query will print the rows that have exactly 2 elements:
select * from test1 group by clientid having count(*) = 2;
If you want 2 or more elements, replace = 2 in the example above with >= 2.
select * from test1 group by clientid having count(*) >= 2;
SELECT clientid, COUNT(clientid) FROM quotation
GROUP BY clientid