Question

I’m not sure if “linearization” is the proper term, but I need a query that will output something like this:

item_name    item_price  first_name  last_name
-----------------------------------------------
'camera'    '100'        'Little'    'Timmy'
'computer'  '200'        'Little'    'Timmy'

Here’s my DB: http://pastebin.com/iS4QKHEb

Any help is greatly appreciated. Thanks.

Answer 1

Here’s:

SELECT MAX(CASE WHEN f.name = 'item_name' THEN fd.value ELSE NULL END) AS item_name,
       MAX(CASE WHEN f.name = 'item_price' THEN fd.value ELSE NULL END) AS item_price,
       MAX(CASE WHEN f.name = 'first_name' THEN fd.value ELSE NULL END) AS first_name,
       MAX(CASE WHEN f.name = 'last_name' THEN fd.value ELSE NULL END) AS last_name
  FROM FIELDDATA fd
  JOIN FIELD f ON f.id = fd.fieldid

But the problem is I don’t see what there is to group by in order to get the two rows you want as output – the datasourceid is the same for all the records, so it can’t be used.

And if you [likely] want this to be dynamic, it’ll require dynamic SQL via MySQL Prepared Statement syntax.