mysql select distinct while ignoring one column - php

Question

I have the following problem: I have a table import_data
The table is enriched something like this
| id | profile_id | sku | vendor | price | importRun |
| 1 | 39 | 123 | myVen | 2.0 | 1 |
| 2 | 39 | 456 | myVen | 2.0 | 1 |
| 3 | 39 | 123 | myVen | 3.0 | 2 |
What I need to get is an output of all elements, but only once. Every sku must be unique. To make it even worse, I need the newest data, if they are redundant.
My output should be like this:
| id | profile_id | sku | vendor | price | importRun |
| 2 | 39 | 456 | myVen | 2.0 | 1 |
| 3 | 39 | 123 | myVen | 3.0 | 2 |
Short Summary about the structure:
ID = PK
sku = a unique identifier for an article
importRun = Needed for comparision.
So, to explain it: I have an import-script, which reads a given CSV-file and imports all articles listed in it. I get this CSV-file in a regular period (once a week). I need to collect all data and save it, to create a price-evolution later on.
After every Import, I increment the number of importRun, so that no information is lost (remember, I can't use REPLACE INTO or INSERT IGNORE.
Now, when I export it, I need the newest Data, if a SKU occures multiple times. In this case, the SKU 123 is inserted 2 times on 2 different runs. That means, since my newest Run had the number 2, I need this tupel (and ignore the first one).
When I work with DISINCT, it would still output the same table, since they aren't distinct at all, because importRun differs.
I should be able to use GROUP BY, but I couldn't figure out which value will be taken, the first- or the last one? (importRun 1 or 2)
Update 1
Followed by the idea of #mitkosoft, I tried the following:
SELECT DISTINCT t1.*
FROM import_data t1
INNER JOIN import_profiles imp on t1.profile_id = imp.id
INNER JOIN (
SELECT DISTINCT sku, MAX(importRun) AS importRun
FROM import_data
GROUP BY sku ) t2
ON t1.sku = t2.sku
WHERE imp.creditornr = 73329
AND t1.vendor = 'rackmountit'
AND t1.importRun = t2.importRun
** Update 2 **
I added the complete Structures for all tables, which are relevant.
Import-Data:
|
Import-Profiles
But i still get duplicates :/

Answer 1

All you need to do is to determine MAX(importRun) for each sku:
SELECT
t1.*
FROM
import_data t1
INNER JOIN (
SELECT sku, MAX(importRun) AS importRun FROM import_data GROUP BY sku
) t2
ON t1.sku = t2.sku
AND t1.importRun = t2.importRun
Output is:
+----+------------+-----+--------+-------+-----------+
| id | profile_id | sku | vendor | price | importRun |
+----+------------+-----+--------+-------+-----------+
| 2 | 39 | 456 | myVen | 2.0 | 1 |
| 3 | 39 | 123 | myVen | 3.0 | 2 |
+----+------------+-----+--------+-------+-----------+
2 rows in set

Answer 2

Perhaps you could join on the same table where sku = sku