I am trying to figure out how to select an item from table by his column name p.e.
strucutre looks like this
table items
id | name | column_1 | column_2 | column_3 |
1 | nm1 | 1 | 4 | 7,8 |
2 | nm2 | 2,3 | 4 | 9 |
3 | nm3 | 3,1 | 4 | 7 |
table columns
id | c_name |
1 | cnm1 |
2 | cnm2 |
3 | cnm3 |
table column_values
id | c_id | value |
1 | 1 | abcd |
2 | 1 | cdbh |
3 | 1 | dsff |
4 | 2 | wewe |
5 | 2 | cgbh |
6 | 2 | cdlh |
7 | 3 | adbh |
8 | 3 | qdbh |
9 | 3 | pdbh |
So when I wanted to find "abcd" I tried
"SELECT a.* FROM items a, columns b, column_values c WHERE c.`value` LIKE '%abcd%' GROUP BY a.`id`"
but I knew this will find nothing without any conections so i went further
"SELECT a.* FROM items a, columns b, column_values c WHERE c.`value` LIKE '%abcd%' AND b.`id` = c.`c_id` GROUP BY a.`id`"
still no proper connection with item
and here is the problem there is a changing amount of columns and the name contains id of the column and value is set of ids of column values.
So i need to select item by his name which is "name+"column_id in column_values by FIND IN SET cause if i look for abcd it is id 1 and there are two items which have id 1 in column_1
item 1 and item 2
ALSO id of values are AI so there is not possibility of duplicate so there is no need to check of column_id to search in proper column in item table
it can work something like for from 0 - 30 p.e. and it will search in column_1, column_2 column_3 until 30 for id match
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'm developing a PHP script, and I have the following table:
+----+-----------+----------+--------------+
| id | id_parent | position | feature |
+----+------------+---------+--------------+
| 1 | 1 | 2 | -B-A-C- |
| 2 | 1 | 3 | -B-C- |
| 3 | 2 | 4 | -C-B- |
| 4 | 3 | 1 | -A-B- |
| 5 | 1 | 6 | -A-C- |
| 6 | 2 | 5 | -C-B- |
| 7 | 2 | 7 | -B-C- |
| 8 | 3 | 8 | -A- |
+----+-----------+----------+--------------+
From this table I would like to select all the rows with "feature" LIKE "%-A-%", but displaying first the result with lowest "position", then all the rows that have same value for column "id_parent" of the first result, then row with the 2nd lowest "position" and all the rows that have same "id_parent" of the result with the 2nd lowest "position", and so on...
So the final result should be:
+----+-----------+----------+--------------+
| id | id_parent | position | feature |
+----+------------+---------+--------------+
| 4 | 3 | 1 | -A-B- |
| 8 | 3 | 8 | -A- |
| 1 | 1 | 2 | -B-A-C- |
| 5 | 1 | 6 | -A-C- |
+----+-----------+----------+--------------+
For some reason I can't explain here I need to have and HAVING clause for selecting the right "feature" value (...HAVING 'feature' LIKE '%-A-%' ...).
Is it possible to make all this with MySQL (possibly without subqueries) or by processing data results with PHP?
Does this help? I've left the last part of the problem as an exercise for the reader...
SELECT a.*
, c.*
FROM my_table a
JOIN
( SELECT id_parent, MIN(position) position FROM my_table WHERE feature = 'a' GROUP BY id_parent ) b
ON b.id_parent = a.id_parent
AND b.position = a.position
JOIN my_table c
ON c.feature = a.feature
AND c.id_parent = a.id_parent;
i have a table with only 2 columns.
for example
table product.combinations
Column 1: product.id
Column 2: attribute.id
Product.id is unique
every product can have 1 or more attributes.
Products without attributes are not in the table
for example
table product.combinations
product.id | attribute.id
1 | 1 |
1 | 2 |
2 | 1 |
2 | 2 |
5 | 1 |
5 | 3 |
9 | 2 |
9 | 3 |
9 | 5 |
Now i would like to do a select with the result below
product.id | attribute1 | attribute2 | attribute3 |attribute 4 | attribute 5
1 | 1 | 2 | | |
2 | 1 | 2 | | |
5 | 1 | 3 | | |
9 | 2 | 3 | 5 | |
i have already tried with a pivot but i was not able to hae o good result.
Can anyone give me a help?
First: DO NOT use dots/periods in table/column names, this won't work, use underscores instead.
Second, if it is ok to have all attribute ids in a comma-separated list, you can do the following (using MySQL's GROUP_CONCAT function):
mysql> SELECT
-> product_id, GROUP_CONCAT(attribute_id ORDER BY attribute_id) AS attributes
-> FROM product_combinations
-> GROUP BY product_id
-> ORDER BY product_id;
+------------+---------------+
| product_id | attributes |
+------------+---------------+
| 1 | 1,2 |
| 2 | 1,2 |
| 5 | 1,3 |
| 9 | 2,3,5 |
+------------+---------------+
4 rows in set (0.00 sec)
SELECT ATTRIBUTE
FROM combinations
UNION ALL
SELECT ATTRIBUTE
FROM combinations
I have a MySQL table that is formatted as follows:
group_clue:
---------------------------------------------------
| id | group_id | clue_id | completed | run_order |
---------------------------------------------------
| 1 | 1 | 2 | 1 | 1 |
| 2 | 1 | 6 | 1 | 2 |
| 3 | 1 | 4 | 1 | 3 |
| 4 | 1 | 3 | 0 | 4 |
| 5 | 1 | 1 | 0 | 5 |
| 6 | 1 | 5 | 0 | 6 |
| 7 | 2 | 9 | 1 | 1 |
| 8 | 2 | 2 | 0 | 2 |
...
---------------------------------------------------
The data above in the group_clue is constructed such that each group_id has every clue_id at some run_order (ranging from 1 to the number of clue_ids and not repeating for a particular group).
First Question
I want to create a table showing the first clue_id for each group_id where completed = 0 when ordered by run_order (aliased as current_clue). Using the above example, this would give:
---------------------------
| group_id | current_clue |
---------------------------
| 1 | 3 |
| 2 | 2 |
---------------------------
My preliminary attempt is:
SELECT group_id, MIN(clue_id) as current_clue
FROM group_clue
WHERE completed = 0
GROUP BY group_id
However, this returns the same clue_id for each group_id.
Second Question
From the data in the first question, I would like to compose a final table where I GROUP_CONCAT() these results so that it contains every current_clue and each group_id that contains that current_clue. I would also like it ordered from those clues with the most group_ids to those with the fewest. An example resulting table is:
--------------------
| clue | group_ids |
--------------------
| 3 | 1,5,4,3 |
| 2 | 2,6 |
--------------------
I cannot figure out the ordering. My preliminary attempt is:
SELECT clue_id, GROUP_CONCAT(group_id)
FROM [resulting_table]
GROUP BY clue_id
ORDER BY [something]
Any help is appreciated: what queries would fit this scenario?
The first part of your question can be solved this way (it expects that run_order is unique per group):
SELECT t1.group_id,
t1.clue_id AS current_clue
FROM group_clue t1
INNER JOIN (SELECT group_id,
MIN(run_order) as run_order
FROM group_clue
WHERE completed = 0
GROUP BY group_id) t2 USING (group_id, run_order)
The logic of this query is pretty simple:
The inner query selects the pairs of group_id and the corresponding minimal value of run_order which has the completed = 0.
After that we join the original table to this set of pairs so that we could select the corresponding clue_id additionally.
You can sort by number of elements per group using
ORDER BY COUNT(*) DESC
My SQL table looks like
+-----+------------+--------------+--------------+-----------+------------+-----------+
| rid | ship_to_id | product_code | product_name | first_row | second_row | third_row |
+-----+------------+--------------+--------------+-----------+------------+-----------+
| 1 | 555 | A | Crystal | 1 | 2 | 3 |
| 1 | 555 | A | Crystal | 4 | 5 | 6 |
| 2 | 333 | B | Diamond | first | second | third |
| 2 | 333 | A | Crystal | ROW 1 | ROW 2 | ROW 3 |
| 2 | 333 | A | Crystal | ROW 4 | ROW 5 | ROW 6 |
+-----+------------+--------------+--------------+-----------+------------+-----------+
And I am trying to get following results
+-----+------------+--------------+-------------------------------------+
| rid | ship_to_id | product_name | data |
+-----+------------+--------------+-------------------------------------+
| 1 | 555 | Crystal | 1 2 3 4 5 6 |
| 2 | 333 | Diamond | first second third |
| 2 | 333 | Crystal | ROW 1 ROW 2 ROW 3 ROW 4 ROW 5 ROW 6 |
+-----+------------+--------------+-------------------------------------+
Can someone please tell me what is wrong with my code. Thanks
$query = mysql_query("SELECT * FROM mytable group by rid, ship_to_id, product_code, product_name");
while($row = mysql_fetch_array($query)) {
echo "$row[rid] $row[ship_to_id] $row[product_code] $row[product_name] $row[first_row] $row[second_row] $row[third_row] <br>";
}
You're forgetting product_code sometimes, I guess.
This probably is bad database design. You should learn about Database normalization and related techniques.
Third, SQL normally produces the same number of columns for every result record, so the best result you could have has rows like 1, 555, "A", "Crystal", "1 4 2 5 3 6" (notice these are 5 values). But I cannot think of a concatenation method that would produce the numbers in the 1 2 3 4 5 6 order. Depending on the better form of your database-schema-to-be, this might be something easier done in PHP than SQL.
If you're still up to concatenating all values into a single cell (as in the newly formatted example output), the you should try something along these lines:
SELECT
rid, ship_to_id, product_code, product_name,
GROUP_CONCAT(CONCAT(first_row,'#',second_row,'#',third_row) SEPARATOR '~') AS data
FROM tablename
GROUP BY rid, ship_to_id, product_code, product_name;
Notice that the values of first_row etc. are separated by a '#' and the values from distinct records by a '~' sign. You can find more options in the documentation of MySQL's GROUP_CONCAT().
you can try something like
select rid,ship_to_id,product_name,
GROUP_CONCAT(CONCAT(first_row,' ',second_row,' ',third_row) as new_val
from mytable
group by rid,ship_to_id,product_name;
As you group by the first 4 columns and use no aggregation function on the remaining ones, data will be lost when multiple record have the same values in the columns grouped by.
So basically the result will be like the following:
+-----+------------+--------------+------------------------------------+
| rid | ship_to_id | product_name | first_row | second_row | thrid_row |
+-----+------------+--------------+------------------------------------+
| 1 | 555 | Crystal | 1 | 2 | 3 |
| 2 | 333 | Diamond | first | second | third |
| 2 | 333 | Crystal | ROW 1 | ROW 2 | ROW 3 |
+-----+------------+--------------+------------------------------------+
That's what group by means. To keep the data of the fields containing varying data, you must use an aggregation function on them, like GROUP_CONCAT. Example:
SELECT rid, ship_to_id, product_code, product_name, GROUP_CONCAT(first_row), GROUP_CONCAT(second_row), GROUP_CONCAT(third_row)
FROM mytable
GROUP BY rid, ship_to_id, product_code, product_name
This will concatenate the values of the corresponding record like this:
+-----+------------+--------------+------------------------------------------+
| rid | ship_to_id | product_name | first_row | second_row | thrid_row |
+-----+------------+--------------+------------------------------------------+
| 1 | 555 | Crystal | 1 4 | 2 5 | 3 6 |
| 2 | 333 | Diamond | first | second | third |
| 2 | 333 | Crystal | ROW 1 ROW 4 | ROW 2 ROW 5 | ROW 3 ROW 6 |
+-----+------------+--------------+------------------------------------------+
However, your approach with GROUP BY is probably not be the best for this case. It would worth to think about to just order by the rid, ship_to_id, product_code, product_name columns, and then iterate through them in PHP with the given order and merge the corresponding rows there.
You may also have to reconsider you database design, as a query like this smells about a bad concept :)