i have this table called bag:
+--------+----------+---------+----------+
| bag_id | chara_id | item_id | item_qty |
+--------+----------+---------+----------+
| 1 | 1 | 2 | 22 |
| 2 | 1 | 1 | 55 |
| 3 | 3 | 1 | 2 |
| 6 | 3 | 4 | 2 |
| 7 | 4 | 4 | 2 |
| 8 | 5 | 4 | 2 |
| 9 | 6 | 4 | 2 |
| 10 | 1 | 5 | 1 |
| 11 | 1 | 2 | 1 |
| 12 | 1 | 2 | 1 |
| 13 | 1 | 2 | 1 |
| 14 | 1 | 8 | 1 |
| 15 | 1 | 6 | 1 |
| 16 | 1 | 8 | 1 |
| 17 | 1 | 6 | 1 |
+--------+----------+---------+----------+
the relationship goes as 1 chara = many item
now i dont want 1 chara = many duplicated item.
how can i make a query that delete's the duplicated values?
like chara_id: 1 has 3 duplicated item_id: 2
i want to delete the other 2.
Not the best way to do it. But the below should definetly work:
Delete from Bag
where bag_id
not in (
select min(bag_id) from bag a,
(select chara_id, item_id
from bag group by chara_id, item_id
having count(*) > 1) b
where a.chara_id = b.chara_id and a.item_id = b.item_id
UNION
select bag_id from bag a,
(select chara_id, item_id
from bag group by chara_id, item_id
having count(*) = 1) b
where a.chara_id = b.chara_id and a.item_id = b.item_id
)
You can simply join table bag with a subquery which gets the minimum bag_id for every combination of chara_ID and item_ID. Records that have null values on any fields on the subquery are the records that will be deleted.
DELETE a
FROM bag a
LEFT JOIN
(
SELECT chara_ID, item_ID, MIN(bag_ID) min_ID
FROM bag
GROUP BY chara_ID, item_ID
) b ON a.bag_ID = b.min_ID AND
a.chara_ID = b.chara_ID AND
a.item_ID = b.item_ID
WHERE b.min_ID IS NULL
SQLFiddle Demo
Related
I wanted to UPDATE the value of my below table (row & col_md) :
Current Data
| id | id_cat | row | col_md |
| --- | ------ | ---- | ------ |
| 1 | 1 | 1 | 4 |
| 2 | 1 | 2 | 5 |
| 3 | 1 | 3 | 5 |
| 4 | 2 | 1 | 3 |
| 5 | 2 | 2 | 4 |
| 6 | 2 | 2 | 4 |
| 7 | 3 | 1 | 12 |
| 8 | 3 | 1 | 12 |
| 9 | 3 | 2 | 3 |
That may look something like the below table. (I want to have the same content of rows that id_cat=1 have, in rows with id_cat=2 & 3).
Required Data:
| id | id_cat | row | col_md |
| --- | ------ | ---- | ------ |
| 1 | 1 | 1 | 4 |
| 2 | 1 | 2 | 5 |
| 3 | 1 | 3 | 5 |
| 4 | 2 | 1 | 4 |
| 5 | 2 | 2 | 5 |
| 6 | 2 | 3 | 5 |
| 7 | 3 | 1 | 4 |
| 8 | 3 | 2 | 5 |
| 9 | 3 | 3 | 5 |
id_cat 2 and 3 should have the same "row" and "col_md" values as in id_cat=1.
I've tried with this post first answer like this:
UPDATE `myTable` AS t1 JOIN `myTable` AS t2 ON t2.id_cat=1
SET t1.row = t2.row, t1.col_md = t2.col_md
WHERE t1.id_cat = 2 or t1.id_cat=3;
but that results on all "row" column values equal to 1.
What I'm doing wrong and what's the way to do this right?
EDIT:
The tables above are just examples to make this ask easier to understand, but the real table is bigger (4k rows) and:
"row" column with id_cat=1 can have any number and not a sequence as in the example.
"col_md" columns can have any number too.
That's why the update must set a copy of the id_cat=1 "row" and "col_md" values in the id_cat!=1 "row" and "col_md" values.
If this can't be done with just MySQL, a php script will be nice too.
In the example query you gave, you are updating t1.row with t2.row. As you are joining on the id_cat, this will result in multiple rows selected to update a single row, so the outcome just takes the first row.
What you actually want, is to make the 1-to-1 relation in the update, so what needs to be changed in your query is to add the row matching in the join and remove the assignment in the SET, like this:
UPDATE `myTable` AS t1 JOIN `myTable` AS t2 ON t2.id_cat=1 AND t1.row = t2.row
SET t1.col_md = t2.col_md
WHERE t1.id_cat = 2 or t1.id_cat=3;
Which then gives the output of:
MariaDB [testart]> select * from myTable;
+------+--------+------+--------+
| id | id_cat | row | col_md |
+------+--------+------+--------+
| 1 | 1 | 1 | 4 |
| 2 | 1 | 2 | 5 |
| 3 | 1 | 3 | 5 |
| 4 | 2 | 1 | 4 |
| 5 | 2 | 2 | 5 |
| 6 | 2 | 3 | 5 |
| 7 | 3 | 1 | 4 |
| 8 | 3 | 1 | 4 |
| 9 | 3 | 2 | 5 |
+------+--------+------+--------+
9 rows in set (0.00 sec)
Currently able to achieve the SQL query for your desired result.
SELECT t2.id_cat, t1.row, t1.col_md
FROM (SELECT row, col_md from mytable WHERE id_cat=1) as t1 , mytable as t2
GROUP BY t2.id_cat, t1.row, t1.col_md
The above will return the following..
I suggest to use INSERT statement along with the above query to put the record into a new table and drop the old one.
Cheers!
EDITED...
Instead of Updating table, alternate approach could be to Insert the required record into a new table.
This can be achieved with following four steps
Create a tmp table with same fileds (id Auto_Increment, id_cat, row, col_md)
Insert to tmp table with this statement...
INSERT INTO tmp(id_cat, row, col_md)
SELECT t2.id_cat, t1.row, t1.col_md
FROM (SELECT row, col_md from mytable WHERE id_cat=1) as t1 , mytable as t2
GROUP BY t2.id_cat, t1.row, t1.col_md
Remove/Rename 'myTable'.
Rename 'tmp' table to 'myTable'.
Hope this will serve the purpose...
Cheers!
it's not enough to tell which group you want the data from, you need to match id to id.
in your case t2.id 4 and 7 to t1.id 1, t2.id 5 and 8 to t1.id 2, and t2.id 6 and 9 to t1.id 3.
SELECT #d := COUNT(*) FROM myTable WHERE id_cat = 1;
UPDATE `myTable` AS t1
JOIN `myTable` AS t2 ON t2.id_cat=1 AND
t2.id = IFNULL(NULLIF(t1.id MOD #d, 0), #d)
SET t1.row = t2.row, t1.col_md = t2.col_md
WHERE t1.id_cat = 2 or t1.id_cat=3;
#d holds the number of lines where id_cat = 1
we divide t1.id by #d and match the remainder (MOD) to t2.id.
when t1.id is multiple of #d the remainder is 0 and we have to match it to #d
so we make 0 into NULL and NULL into #d
In my understanding, the difficult part about this question is to relate each record to update (ie each record with id_cat IN (2, 3)) to the relevant original record (record with id_cat = 1).
Based on your sample data, I understand that you expect series of records for each id_cat (I can see three groups of three records, sorted by increasing id), so I would assume that you want to relate each record to the original that has the same sequence in the group of record where id_cat = 1.
Assuming MySQL 8.0, a typical approach to assign a number to a record within a group is ROW_NUMBER(). Consider this simple query:
SELECT
t.*,
ROW_NUMBER() OVER(PARTITION BY id_cat ORDER BY id) rn
FROM t
Yields:
| id | id_cat | rw | col_md | rn |
| --- | ------ | --- | ------ | --- |
| 1 | 1 | 1 | 4 | 1 |
| 2 | 1 | 2 | 5 | 2 |
| 3 | 1 | 3 | 5 | 3 |
| 4 | 2 | 1 | 3 | 1 |
| 5 | 2 | 2 | 4 | 2 |
| 6 | 2 | 2 | 4 | 3 |
| 7 | 3 | 1 | 12 | 1 |
| 8 | 3 | 1 | 12 | 2 |
| 9 | 3 | 2 | 3 | 3 |
Now with this set-up in mind, we can turn this query to a Common Table Expression (available also starting MySQL 8.0), and JOIN it as need with the original table to do the UPDATE:
WITH cte AS (
SELECT
t.*,
ROW_NUMBER() OVER(PARTITION BY id_cat ORDER BY id) rn
FROM t
)
UPDATE t t0
INNER JOIN cte t1 ON t1.id = t0.id
INNER JOIN cte t2 ON t2.id_cat = 1 AND t2.rn = t1.rn
SET t0.rw = t2.rw, t0.col_md = t2.col_md
WHERE t0.id_cat IN (2, 3)
Details:
t0 is the original table, where records having id_cat IN (2, 3) need to be updated
t1 is the corresponding record in the CTE (to which a row number was assigned)
t2 is the record in the CTE that has id_cat = 1 and the same row number as the record being updated
Demo on DB Fiddle:
| id | id_cat | rw | col_md |
| --- | ------ | --- | ------ |
| 1 | 1 | 1 | 4 |
| 2 | 1 | 2 | 5 |
| 3 | 1 | 3 | 5 |
| 4 | 2 | 1 | 4 |
| 5 | 2 | 2 | 5 |
| 6 | 2 | 3 | 5 |
| 7 | 3 | 1 | 4 |
| 8 | 3 | 2 | 5 |
| 9 | 3 | 3 | 5 |
I got to table need to combine into 1
Table 1 :
| ID | FEEDBACK_VALUE |
| 1 | EMAILS |
| 2 | WALK IN |
| 3 | SMS BLAST |
| 4 | SOCIAL MEDIA |
| 5 | NEWSPAPER |
| 6 | FAMILY & FRIEND |
| 7 | OTHERS |
Table 2 :
| ID | FEEDBACK_ID |
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 7 |
| 5 | 7 |
| 6 | 7 |
| 7 | 4 |
| 8 | 4 |
| 9 | 3 |
Table 3 :
| ID | FEEDBACK_VALUE | FEEDBACK_RECEIVE |
| 1 | EMAILS | 1 |
| 2 | WALK IN | 2 |
| 3 | SMS BLAST | 1 |
| 4 | SOCIAL MEDIA | 2 |
| 5 | NEWSPAPER | 0 |
| 6 | FAMILY & FRIEND | 0 |
| 7 | OTHERS | 3 |
From table 1 and 2, How can i get result like table 3 using mysql? Thanks
You could use a left jojn, and subquery with count group by
select t1.ID, t1.FEEDBACK_VALUE, ifnull( my_count,0) feedback_receive
from table1 t1
left join (
select FEEDBACK_ID, count(*) as my_count
from table 2
group by FEEDBACK_ID
) t on t1.ID = t.FEEDBACK_ID
Just use a subquery as shown below:
SELECT A.*, (SELECT COUNT(*) FROM TABLE2 B WHERE A.ID=B.FEEDBACK_ID) AS FEEDBACK_RECEIVE
FROM TABLE1 A;
See DEMO on SQL Fiddle
Or, if less code is your thing...
SELECT x.*
, COUNT(y.id) total
FROM table_1 x
LEFT
JOIN table_2 y
ON y.feedback_id = x.id
GROUP
BY x.id;
I have two tables:
table pin_info:
id | member_id | look_week | look_name | is_pinned | date
1 | 1 | 3 | the improviser | yes | 2013-11-19 21:57:04
2 | 1 | 2 | destined for stardom | yes | 2013-11-19 21:56:00
3 | 1 | 1 | fashinably corporate | no | 2013-11-19 21:54:00
table arrow_rating:
id | member_id | look_week | look_name | rating |
1 | 1 | 3 | the improviser | 3 |
2 | 1 | 2 | destined for stardom | 4 |
3 | 2 | 1 | fashinably corporate | 5 |
I want is_pinned(from pin_info) and rating(from rating) .I will be having parameter member_id and look_week. (assume 1 and 2 respectively)
What I have done:
SELECT p_i.is_pinned,a_r.rating
FROM pin_info p_i,arrow_rating a_r
WHERE p_i.look_week=a_r.look_week AND p_i.member_id='1'
I am sure this is not the correct way.Any help?
Try this:
SELECT pin_info.is_pinned, arrow_rating
FROM pin_info INNER JOIN arrow_rating
ON pin_info.look_week = arrow_rating.look_week
WHERE pin_info.id = '1';
SELECT is_pinned, rating
FROM pin_info
LEFT JOIN arrow_rating USING (look_week, member_id)
WHERE pin_info.member_id = 1
AND pin_info.look_week = 2
That will select where both member_ids equal 1, and look_week equals 2
The result set for the above is:
is_pinned | rating
------------------
yes | 4
I have a query that needs a custom sorting, trimmed down to the bare minimums something like:
SELECT u.*, p.*, p.id as product_id
FROM users u, products p
WHERE u.id = p.user_id
ORDER BY product_id DESC
And I get returned a set of rows like:
UserID ProductID
2 5
2 4
3 3
1 2
1 1
But I want it to actually sort SOMETHING like this (so no 2 UserIDs are adjacent to eachother):
UserID ProductID
1 2
2 4
3 3
2 5
1 1
Is this even possible with MySQL, or do I need some PHP magic?
A canonical way of solving this problem is by enumerating the duplicate rows and then ordering by that value:
select t.*
from (SELECT u.*, p.*, p.id as product_id,
row_number() over (partition by u.id order by (select NULL)) as seqnum
FROM users u join
products p
on u.id = p.user_id
) t
order by seqnum, id;
This will work, as long as no one user has a really long sequence (as in your example).
There is no "always-works" solution, because it is easy to come up with a situation where your goal is not possible.
Here fetch your sorted results into an array. Then do something like this.
$records = $res->fetchAll();
$count = count($records);
$records = array_chunk($records, ceil(count($records)/2);
$unsorted = array();
for($x = 0; $x < $count; $x++){
$unsorted[] = $records[$x%2][floor($x/2)];
}
Consider the following...
CREATE TABLE sortable(id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,player_id INT NOT NULL);
INSERT INTO sortable(player_id) VALUES (1),(1),(2),(3),(4),(3),(3),(2),(1),(2),(4),(4);
SELECT * FROM sortable;
+----+-----------+
| id | player_id |
+----+-----------+
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 4 |
| 6 | 3 |
| 7 | 3 |
| 8 | 2 |
| 9 | 1 |
| 10 | 2 |
| 11 | 4 |
| 12 | 4 |
+----+-----------+
SELECT x.*,COUNT(*) rank FROM sortable x JOIn sortable y ON y.player_id = x.player_id AND y.id <= x.id GROUP BY x.id ORDER BY player_id,rank;
+----+-----------+------+
| id | player_id | rank |
+----+-----------+------+
| 1 | 1 | 1 |
| 2 | 1 | 2 |
| 9 | 1 | 3 |
| 3 | 2 | 1 |
| 8 | 2 | 2 |
| 10 | 2 | 3 |
| 4 | 3 | 1 |
| 6 | 3 | 2 |
| 7 | 3 | 3 |
| 5 | 4 | 1 |
| 11 | 4 | 2 |
| 12 | 4 | 3 |
+----+-----------+------+
SELECT x.*,COUNT(*) rank FROM sortable x JOIn sortable y ON y.player_id = x.player_id AND y.id <= x.id GROUP BY x.id ORDER BY rank;
+----+-----------+------+
| id | player_id | rank |
+----+-----------+------+
| 1 | 1 | 1 |
| 3 | 2 | 1 |
| 4 | 3 | 1 |
| 5 | 4 | 1 |
| 2 | 1 | 2 |
| 8 | 2 | 2 |
| 6 | 3 | 2 |
| 11 | 4 | 2 |
| 9 | 1 | 3 |
| 10 | 2 | 3 |
| 7 | 3 | 3 |
| 12 | 4 | 3 |
+----+-----------+------+
So if your problem is just that you dont want two records with same id should not come next to each other wha I can think simplest is use
SELECT u.*, p.*, p.id as product_id
FROM users u, products p
WHERE u.id = p.user_id
ORDER BY user_id%2 DESC
Or you can even use other number than 2 to meet any certain order you want....
My table has 4 tags linked to the to each id. I want to select the position(rank) of that value(tag_name or tag_id) and the number of times the value(tag_name or tag_id) displays in that same position(rank).
Here's what it would look like in mysql:
> +--------+------------+--------+------+
> | id | tag_name | tag_id | rank |
> +--------+------------+--------+------+
> | 2345 | cookie | 2 | 1 |
> | 2345 | bar | 1 | 2 |
> | 2345 | cereal | 3 | 3 |
> | 2345 | milk | 4 | 4 |
> | 2346 | cereal | 3 | 1 |
> | 2346 | milk | 4 | 2 |
> | 2346 | cookie | 2 | 3 |
> | 2346 | hot dogs | 5 | 4 |
> | 2347 | chocolate | 6 | 1 |
> | 2347 | bar | 1 | 2 |
> +--------+------------+--------+------+
Here's what my current code looks like:
SELECT m.*, tr.tag_id, t.tag_name, #rownum:=#rownum + 1 AS rank
FROM meals AS m
RIGHT JOIN tags_rel AS tr ON tr.meal_id = m.id
JOIN tags AS t ON tr.tag_id = t.id
JOIN (SELECT #rownum:=0) AS r
ORDER BY m.id DESC
Please keep in mind that I'm actually using a pagination so my ORDER BY actually looks like this:
ORDER BY id DESC LIMIT $start_from, 12
If I select either tag_name=bar or tag_id=1 and rank=2 I should get the bellow results. Plus I would like the count of rows returned for that value.
> +--------+------------+--------+------+
> | id | tag_name | tag_id | rank |
> +--------+------------+--------+------+
> | 2345 | bar | 1 | 2 |
> | 2347 | bar | 1 | 2 |
> +--------+------------+--------+------+
Thanks!
SELECT tag_name, tag_id, rank, COUNT(tag_id) AS rankcount
FROM table
GROUP BY tag_id, rank;
results in:
+-----------+--------+------+-----------+
| tag_name | tag_id | rank | rankcount |
+-----------+--------+------+-----------+
| bar | 1 | 2 | 2 |
| cookie | 2 | 1 | 1 |
| cookie | 2 | 3 | 1 |
| cereal | 3 | 1 | 1 |
| cereal | 3 | 3 | 1 |
| milk | 4 | 2 | 1 |
| milk | 4 | 4 | 1 |
| hot dogs | 5 | 4 | 1 |
| chocolate | 6 | 1 | 1 |
+-----------+--------+------+-----------+
9 rows in set (0.00 sec)
If you want your original table enhanced by a count of lines (although that seems to be quite senseless, as every sql result returns the number of rows) you'll have to do a subquery:
SELECT id, tag_name, tag_id as t_id, rank,
(SELECT count(tag_id) FROM table WHERE tag_id = t_id) as subqueryCount
FROM table;
+------+-----------+------+------+---------------+
| id | tag_name | t_id | rank | subqueryCount |
+------+-----------+------+------+---------------+
| 2345 | cookie | 2 | 1 | 2 |
| 2345 | bar | 1 | 2 | 2 |
| 2345 | cereal | 3 | 3 | 2 |
| 2345 | milk | 4 | 4 | 2 |
| 2346 | cereal | 3 | 1 | 2 |
| 2346 | milk | 4 | 2 | 2 |
| 2346 | cookie | 2 | 3 | 2 |
| 2346 | hot dogs | 5 | 4 | 1 |
| 2347 | chocolate | 6 | 1 | 1 |
| 2347 | bar | 1 | 2 | 2 |
+------+-----------+------+------+---------------+
10 rows in set (0.00 sec)
Extending that query would result in your desired result, extended by a column where the count of rows is inserted (which is IMO still rather senseless).
SELECT id, tag_name, tag_id as t_id, rank,
(SELECT count(tag_id) FROM table WHERE tag_id = t_id) as subqueryCount
FROM table
WHERE tag_id = 1;
results in
+------+----------+------+------+---------------+
| id | tag_name | t_id | rank | subqueryCount |
+------+----------+------+------+---------------+
| 2345 | bar | 1 | 2 | 2 |
| 2347 | bar | 1 | 2 | 2 |
+------+----------+------+------+---------------+
2 rows in set (0.00 sec)
how about this:
SELECT DISTINCT meal_id as MealId, t2name as TagName, t2id as TagId, Rank
FROM
(SELECT t1id as t2id, t1name as t2name, rnk as rnk2, count(*) as Rank
FROM
tags_rel AS r,
(SELECT m1id, t1id, t1name,
#rnk := CASE WHEN #id <> m1id THEN 1 ELSE #rnk + 1 END AS rnk, #id := m1id as idx
FROM
tags_rel AS r,
(SELECT #id := 0) idx,
(SELECT #rnk := 0) rxx,
(SELECT m.id AS m1id, t.id AS t1id, name AS t1name
FROM tags_rel r
JOIN (meals AS m, tags AS t ) ON ( m.id = r.meal_id AND t.id = r.tag_id )
) AS rn
WHERE r.tag_id = t1id AND r.meal_id = m1id
ORDER BY m1id, t1name
) AS rno
WHERE r.tag_id = t1id AND r.meal_id = m1id
group BY t1id, t1name, rnk
) as rn2
join (meals, tags_rel) on (meals.id = tags_rel.meal_id and tags_rel.tag_id = t2id)
ORDER BY meal_id, t2id
which results in:
2345 bar 1 2
2345 cookie 2 1
2345 cereal 3 1
2345 milk 4 2
2346 cookie 2 1
2346 cereal 3 1
2346 milk 4 2
2346 hotdog 5 1
2347 bar 1 2
2347 chocolad 6 1