my sql table like given below
Table name package
pack_id pack_name
------- ---------
1 pack1
2 pack2
3 pack3
Table name items
items_id pack_id items_name pack_name
-------- ------- ---------- ---------
1 1 cat pack1
2 1 dog pack1
3 1 cow pack1
4 2 dog pack2
5 2 cow pack2
6 3 cat pack3
In html I want to show the packages like
Pack1 cat dog cow
pack2 dog cow
pack3 cat
Here first
(items_name)cat = 1(items_id) ,
(items_name)dog = 2(items_id) ,
(items_name)cow = 3(items_id) and then
(items_name)dog = 4(items_id) ,
(items_name)cow = 5(items_id) ans also
(items_name)cat = 6(items_id) like this
here I click the cat means corresponding cat id stored in another table.
You seem to want a variable number of columns which isn't really possible. Could maybe do it if there were a fairly limited number of possible columns.
For flexibility probably best to put the item names in a single column in the results, comma separated:-
SELECT a.pack_name, GROUP_CONCAT(b.items_name )
FROM package a
INNER JOIN items b
ON a.pack_id = b.pack_id
GROUP BY a.pack_id
If you really wanted them in columns and only have a limited number of columns then you could maybe do something like this:-
SELECT a.pack_name, MAX(Col0), MAX(Col1), MAX(Col2), MAX(Col3)
FROM package a
INNER JOIN
(
SELECT items_id, pack_id, IF(aSequence=0, items_name, NULL) AS Col0, IF(aSequence=1, items_name, NULL) AS Col1, IF(aSequence=2, items_name, NULL) AS Col2, IF(aSequence=3, items_name, NULL) AS Col3
FROM
(
SELECT items_id, pack_id, items_name, @sequence := IF(@prevpack = pack_id, @sequence + 1, 0) AS aSequence, @prevpack := pack_id
FROM
(
SELECT items_id, pack_id, items_name
FROM items
ORDER BY pack_id, items_id
) Sub1
CROSS JOIN (SELECT @sequence:=0, @prevpack:=0) Sub2
) Sub3
) b
ON a.pack_id = b.pack_id
GROUP BY a.pack_id
But this is hardly readable or efficient. It would also be a pain as you would need to modify it when the max number of columns increases.
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