SQL - Get multiple values when limit 1 - php

If I have a table like this:
ID | ident | product
1 | cucu1 | 99867 |
2 | kkju7 | 88987 |
3 | sjdu4 | 66754 |
4 | kjhu6 | 76654 |
5 | cucu1 | 98876 |
And use this query: SELECT ident,COUNT(*) FROM sales WHERE status=? AND team=? AND DATE(date) = DATE(NOW() - INTERVAL 1 DAY) GROUP BY ident order by COUNT(*) DESC LIMIT 1
I get the value: cucu1, since that has the most rows.
But if my table is like this:
ID | ident | product
1 | cucu1 | 99867 |
2 | kkju7 | 88987 |
3 | sjdu4 | 66754 |
4 | kkju7 | 76654 |
5 | cucu1 | 98876 |
It should return both cucu1 and kkju7, since they are the highest with same count, but still it gives me only cucu1. What am I doing wrong?

You can use rank():
SELECT ident, cnt
FROM (SELECT ident, COUNT(*) as cnt,
RANK() OVER (ORDER BY COUNT(*) DESC) as seqnum
FROM sales
WHERE status = ? AND team = ? AND
DATE(date) = DATE(NOW() - INTERVAL 1 DAY)
GROUP BY ident
) i
WHERE seqnum = 1;

LIMIT keyword simply limits the results to 1 row, no matter if there are equal values before or after the returned row.
A better solution would be to select the rows which have a count that's equal to max count in the query, which can be achieved by the following query:
SELECT ident,COUNT(*)
FROM sales
WHERE status=?
AND team=?
AND DATE(date) = DATE(NOW() - INTERVAL 1 DAY)
GROUP BY ident
HAVING COUNT(*) = MAX(COUNT(*))

Related

Get rows above and below (neighbouring rows) a certain row, based on two criteria SQL

Say I have a table like so:
+---+-------+------+---------------------+
|id | level |score | timestamp |
+---+-------+------+---------------------+
| 4 | 1 | 70 | 2021-01-14 21:50:38 |
| 3 | 1 | 90 | 2021-01-12 15:38:0 |
| 1 | 1 | 20 | 2021-01-14 13:10:12 |
| 5 | 1 | 50 | 2021-01-13 12:32:11 |
| 7 | 1 | 50 | 2021-01-14 17:15:20 |
| 8 | 1 | 55 | 2021-01-14 09:20:00 |
| 10| 2 | 99 | 2021-01-15 10:50:38 |
| 2 | 1 | 45 | 2021-01-15 10:50:38 |
+---+-------+------+---------------------+
What I want to do is show 5 of these rows in a table (in html), with a certain row (e.g. where id=5) in the middle and have the two rows above and below it (in the correct order). Also where level=1. This will be like a score board but only showing the user's score with the two above and two below.
So because scores can be the same, the timestamp column will also need to be used - so if two scores are equal, then the first person to get the score is shown above the other person.
E.g. say the user is id=5, I want to show
+---+-------+------+---------------------+
|id | level |score | timestamp |
+---+-------+------+---------------------+
| 4 | 1 | 70 | 2021-01-14 21:50:38 |
| 8 | 1 | 55 | 2021-01-14 09:20:00 |
| 5 | 1 | 50 | 2021-01-13 12:32:11 |
| 7 | 1 | 50 | 2021-01-14 17:15:20 |
| 2 | 1 | 45 | 2021-01-15 10:50:38 |
| 1 | 1 | 20 | 2021-01-14 13:10:12 |
+---+-------+------+---------------------+
Note that id=7 is below id=5
I am wondering does anyone know a way of doing this?
I have tried this below but it is not outputting what I need (it is outputting where level_id=2 and id=5, and the other rows are not in order)
((SELECT b.* FROM table a JOIN table b ON b.score > a.score OR (b.score = a.score AND b.timestamp < a.timestamp)
WHERE a.level_id = 1 AND a.id = 5 ORDER BY score ASC, timestamp DESC LIMIT 3)
UNION ALL
(SELECT b.* FROM table a JOIN table b ON b.score < a.score OR (b.score = a.score AND b.timestamp > a.timestamp)
WHERE a.level_id = 1 AND a.id = 5 ORDER BY score DESC, timestamp ASC LIMIT 2))
order by score
If it is easier to output all rows in the table, say where level = 1, so it is a full score board.. and then do the getting a certain row and two above and below it using PHP I'd also like to know please :) ! (possibly thinking this may keep the SQL simpler)?
You can use cte and inner join as follows:
With cte as
(select t.*,
dense_rank() over (order by score) as dr
from your_table t)
Select c.*
From cte c join cte cu on c.dr between cu.dr - 2 and cu.dr + 2
Where cu.id = 5
Ordwr by c.dr, c.timestamp
I would suggest window functions:
select t.*
from (select t.*,
max(case when id = 7 then score_rank end) over () as id_rank
from (select t.*,
dense_rank() over (order by score) as score_rank
from t
where level = 1
) t
) t
where score_rank between id_rank - 2 and id_rank + 2;
Note: This returns 5 distinct score values, which may result in more rows depending on duplicates.
Here is a db<>fiddle.
EDIT:
If you want exactly 5 rows using the timestamp, then:
select t.*
from (select t.*,
max(case when id = 7 then score_rank end) over () as id_rank
from (select t.*,
dense_rank() over (order by score, timestamp) as score_rank
from t
where level = 1
) t
) t
where score_rank between id_rank - 2 and id_rank + 2
order by score;
Note: This still treats equivalent timestamps as the same, but they seem to be unique in your data.

SELECT, group, limit based on month

Currently I am using this: SELECT ident,COUNT(*) FROM sales GROUP BY ident order by COUNT(*) DESC LIMIT 3.
I use that to group each ident from sales table, and count the number of rows for each ident, and limit this to 3 rows. Now I want to only select the rows that were added the current month.
This is how the table looks like, sales table:
| ID | ident | prdnr | transfer |
| 1 | HD762 | 7362781 | 2020-08-10 16:25:26 |
| 2 | JJ313 | 4563456 | 2020-08-08 16:25:26 |
| 3 | HD762 | 4363453 | 2020-08-08 16:25:26 |
| 4 | JJ313 | 2326256 | 2020-08-08 16:25:26 |
| 5 | HD762 | 8356345 | 2020-08-07 16:25:26 |
| 6 | JJ844 | 3473563 | 2020-08-07 16:25:26 |
I think this should be the correct query:
SELECT ident,COUNT(*) FROM sales WHERE MONTH(transfer) = MONTH(CURRENT_DATE()) AND YEAR(transfer) = YEAR(CURRENT_DATE()) GROUP BY ident order by COUNT(*) DESC LIMIT 3
Somehow this does not gives me the correct count. What am I doing wrong?
Based on your requirement , a simple way is getting the MySQL current time and subtract a month to get the values
The code :-
SELECT ident,COUNT() FROM sales WHERE transfer > date_sub(now(),
interval 1 month) GROUP BY ident order by COUNT() DESC LIMIT 3;
The output from the query
HD762 3
JJ313 2
JJ844 1
Please let me know if this is the expected result you're looking for.
Reference :-
https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html

How to compare columns values with sum function in SQL?

I have three tables :
mls_category
points_martix
mls_entry
My first table (mls_category) is like below:
*--------------------------------*
| cat_no | store_id | cat_value |
*--------------------------------*
| 10 | 101 | 1 |
| 11 | 101 | 4 |
*--------------------------------*
My second table (points_martix) is like below:
*----------------------------------------------------*
| pm_no | store_id | value_per_point | max_distance |
*----------------------------------------------------*
| 1 | 101 | 1 | 10 |
| 2 | 101 | 2 | 50 |
| 3 | 101 | 3 | 80 |
*----------------------------------------------------*
My third table (mls_entry) is like below:
*-------------------------------------------*
| user_id | category | distance | status |
*-------------------------------------------*
| 1 | 10 | 20 | approved |
| 1 | 10 | 30 | approved |
| 1 | 11 | 40 | approved |
*-------------------------------------------*
I am using the following query to show the sum of distance with some condition:
SELECT SUM(t1.totald/c.cat_value)
AS total_distance
FROM mls_category c
JOIN
(SELECT SUM(distance) totald, user_id, category
FROM mls_entry
WHERE user_id = 1
AND status = 'approved'
GROUP BY user_id, category) t1
ON c.cat_no = t1.category
This gives me sum 60 as total_distance, that is correct which I wanted.
Now, I want to include the third table (points_matrix) and want to compare my sum(60) is less than or equal to 80(max_distance) then my new value would be 60*3=180.
So, suppose my sum comes 10 then my new value will be 10*1=10 and if my sum comes 25 then my new value will be according to point matrix 25*2=50.
Yon can using MIN() to calculate what value_per_point you need, and the whole sql is like this:
SELECT MIN(b.value_per_point) * d.total_distance FROM points_matrix b
JOIN
(
SELECT store_id, sum(t1.totald/c.cat_value) as total_distance FROM mls_category c
JOIN
(
SELECT SUM(distance) totald, user_id, category FROM mls_entry
WHERE user_id= 1 AND status = 'approved' GROUP BY user_id, category
) t1 ON c.cat_no = t1.category
) d ON b.store_id = d.store_id AND b.max_distance >= d.total_distance
Use Correlated Subquery:
SELECT
dt.total_distance * dt.max_points
FROM (
SELECT SUM(t1.totald/c.cat_value) AS total_distance,
(
SELECT value_per_point
FROM points_martix
WHERE SUM(t1.totald/c.cat_value) >= max_distance
ORDER BY max_distance ASC LIMIT 1
) AS max_points
FROM mls_category AS c
JOIN (
SELECT SUM(distance) AS totald,
user_id,
category
FROM mls_entry
WHERE user_id= 1 AND
status = 'approved'
GROUP BY user_id, category
) AS t1 on c.cat_no = t1.category
) AS dt

Two mysql selects in one query - one after another

I have a mysql table like this:
+----+------+
| id | rank |
+----+------+
| 1 | 2 |
+----+------+
| 2 | -1 |
+----+------+
| 3 | 5 |
+----+------+
| 4 | 1 |
+----+------+
| 5 | -1 |
+----+------+
| 6 | -1 |
+----+------+
| 7 | 8 |
+----+------+
| 8 | -1 |
+----+------+
Now I want to get the ids in the following order: At first
WHERE rank >= 1 ORDER BY rank ASC
and afterwards:
WHERE rank = -1
How can I get this in only one mysql_query()?
Try something like:
SELECT *
FROM mytable
WHERE rank >= 1
ORDER BY rank
UNION
SELECT *
FROM mytable
WHERE rank = -1
OR something like:
SELECT *
FROM mytable
WHERE rank >= 1
ORDER BY CASE WHEN rank>=1
THEN 0
ELSE 1,rank
Proposed answer:
SELECT id FROM myTable WHERE rank >= 1 ORDER BY rank ASC
UNION
SELECT id FROM myTable WHERE rank = -1
From my understanding, you wanted a column of id's, starting with the ids WHERE rank >= 1 ORDER BY rank ASC and ending with the ids WHERE rank = -1.
The previous sql query uses UNION which joins two resulting tables from separate SELECT queries. UNION can only be applied when you have the same mount of generated columns from each SELECT query, so that's a good thought to keep in mind if later you want to increase the amount of columns obtained.
You can also map rank with ELT.
sample
SELECT *
FROM mytable
ORDER BY ELT(rank+2,99,0,1,2,3,4,5,6,7,8) ASC;

MySQL get the sum of all rows without retrieving all of them

This may be a little confusing but please bear with me. Here's the thing:
I have a database that contains ~1000 records, as the following table illustrates:
+------+----------+----------+
| id | date | amount |
+------+----------+----------+
| 0001 | 14/01/15 | 100 |
+------+----------+----------+
| 0002 | 14/02/04 | 358 |
+------+----------+----------+
| 0003 | 14/05/08 | 1125 |
+------+----------+----------+
What I want to do is this:
Retrieve all the records beginning at 2014 and until yesterday:
WHERE `date` > '14-01-01' AND `date` < CURDATE()
But also get the sum of amount up to the current date, this is:
WHERE `date` < CURDATE()
I've already got this working by just selecting all the records based on the second condition, getting the sum, and then excluding those which don't match the first condition. Something like this:
SELECT `id`, `date`, `amount` FROM `table`
WHERE `date` < CURDATE()
And then:
$rows = fetchAll($PDOStatement);
foreach($rows as $row) {
$sum += $row->amount;
if (
strtotime($row->date) > strtotime('14-01-01') &&
strtotime($row->date) < strtotime(date('Y-m-d'))
) {
$valid_rows[] = $row;
}
}
unset $rows;
Is there a way to achieve this in a single query, efficiently? Would a transaction be more efficient than sorting out the records in PHP? This has to be SQL-standard compliant (I'll be doing this on MySQL and SQLite).
Update:
It doesn't matter if the result ends up being something like this:
+------+----------+----------+-----+
| id | date | amount | sum |
+------+----------+----------+-----+
| 0001 | 14/01/15 | 100 | 458 |
+------+----------+----------+-----+
| 0002 | 14/02/04 | 358 | 458 |
+------+----------+----------+-----+
| 0003 | 14/05/08 | 1125 | 458 |
+------+----------+----------+-----+
The worst case would be when the resulting set ends up being the same as the set that gives the sum (in this case appending the sum would be irrelevant and would cause an overhead), but for any other regular cases the bandwith save would be huge.
You can create a special record with your sum and add it at the end of your first query
SELECT * FROM `table` WHERE `date` > '14-01-01' AND `date` < CURDATE()
UNION
SELECT 9999, CURDATE(), SUM(`amount`) FROM `table` WHERE `date` < CURDATE()
Then you will have all your desired record and the record with id 9999 or whatever is your sum
This could be achieved by correlated subquery, something like below:
SELECT *, (SELECT SUM(amount) FROM t WHERE t.date < t1.date) AS PrevAmount
FROM t AS t1
WHERE `date` > '14-01-01' AND `date` < CURDATE()
However it is very unefficient if the number of records is large.
It's hackish, but:
> select * from foo;
+------+------+
| id | val |
+------+------+
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 5 |
+------+------+
5 rows in set (0.02 sec)
> select * from foo
left join (
select sum(val)
from foo
where id < 3
) AS bar ON 1=1
where id < 4;
+------+------+----------+
| id | val | sum(val) |
+------+------+----------+
| 1 | 1 | 3 |
| 2 | 2 | 3 |
| 3 | 3 | 3 |
+------+------+----------+
Basically, do your summing in a joined subquery. That'll attach the sum result to every row in the outer table's results. You'll waste a bit of bandwidth sending that duplicated value out with every row, but it does get you the results in a "single" query.
EDIT:
You can get the SUM using a LEFT OUTER JOIN.
SELECT t1.`id`, t1.`date`, t2.sum_amount
FROM
`table` t1
LEFT OUTER JOIN
(
SELECT SUM(`amount`) sum_amount
FROM `table`
WHERE `date` < CURDATE()
) t2
ON 1 = 1
WHERE t1.`date` > STR_TO_DATE('01,1,2014','%d,%m,%Y') AND t1.`date` < CURDATE();
This will do what you want it to do...optimizing the subquery is the real challenge:
SELECT id,date,amount,(SELECT SUM(amount) FROM table) AS total_amount
FROM table
WHERE date BETWEEN '14-01-01' AND DATE_ADD(CURDATE(), INTERVAL -1 DAY)

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