Combine Multiple child rows into one row MYSQL
Thanks in advance, I just can't seem to get it!
I have two tables
Ordered_Item
ID | Item_Name 1 | Pizza 2 | Stromboli
Ordered_Options
Ordered_Item_ID | Option_Number | Value 1 43 Pepperoni 1 44 Extra Cheese 2 44 Extra Cheese
What I am looking to output is a mysql query is something to this effect
Output
ID | Item_Name | Option_1 | Option_2 1 Pizza Pepperoni Extra Cheese 2 Stromboli NULL Extra Cheese
I have tried numerous options most ending in syntax error, I have tried group_concat but thats not really what I am looking for. I have a crude example below of what I think might be a start. I need the options to be in the same order every time. And in the program where the info is collected there is no way to reliable ensure that will happen. Is it possible to have them concatenate according to option number. Also I know that I will never have over 5 options so a static solution would work
Select Ordered_Items.ID,
Ordered_Items.Item_Name,
FROM Ordered_Items
JOIN (SELECT Ordered_Options.Value FROM Ordered_Options Where Option_Number = 43) as Option_1
ON Ordered_Options.Ordered_Item_ID = Ordered_Item.ID
JOIN (SELECT Ordered_Options.Value FROM Ordered_Options Where Option_Number = 44) as Option_2
ON Ordered_Options.Ordered_Item_ID = Ordered_Item.ID;
Thanks! Joe
The easiest way would be to make use of the GROUP_CONCAT group function here..
select
ordered_item.id as `Id`,
ordered_item.Item_Name as `ItemName`,
GROUP_CONCAT(Ordered_Options.Value) as `Options`
from
ordered_item,
ordered_options
where
ordered_item.id=ordered_options.ordered_item_id
group by
ordered_item.id
Which would output:
Id ItemName Options
1 Pizza Pepperoni,Extra Cheese
2 Stromboli Extra Cheese
That way you can have as many options as you want without having to modify your query.
Ah, if you see your results getting cropped, you can increase the size limit of GROUP_CONCAT like this:
SET SESSION group_concat_max_len = 8192;
I appreciate the help, I do think I have found a solution if someone would comment on the effectiveness I would appreciate it. Essentially what I did is. I realize it is somewhat static in its implementation but I does what I need it to do (forgive incorrect syntax)
SELECT
ordered_item.id as `Id`,
ordered_item.Item_Name as `ItemName`,
Options1.Value
Options2.Value
FROM ORDERED_ITEMS
LEFT JOIN (Ordered_Options as Options1)
ON (Options1.Ordered_Item.ID = Ordered_Options.Ordered_Item_ID
AND Options1.Option_Number = 43)
LEFT JOIN (Ordered_Options as Options2)
ON (Options2.Ordered_Item.ID = Ordered_Options.Ordered_Item_ID
AND Options2.Option_Number = 44);
If you really need multiple columns in your result, and the amount of options is limited, you can even do this:
select
ordered_item.id as `Id`,
ordered_item.Item_Name as `ItemName`,
if(ordered_options.id=1,Ordered_Options.Value,null) as `Option1`,
if(ordered_options.id=2,Ordered_Options.Value,null) as `Option2`,
if(ordered_options.id=43,Ordered_Options.Value,null) as `Option43`,
if(ordered_options.id=44,Ordered_Options.Value,null) as `Option44`,
GROUP_CONCAT(if(ordered_options.id not in (1,2,43,44),Ordered_Options.Value,null)) as `OtherOptions`
from
ordered_item,
ordered_options
where
ordered_item.id=ordered_options.ordered_item_id
group by
ordered_item.id