how to combine not null columns in query?

I have a table with only a full column in each row And the rest of the columns are null as follows:

+--------------------------------------------------------------------------------+
|   f_id    |   cloumn1   |     cloumn2     |       cloumn3    |    cloumn4      |
----------------------------------------------------------------------------------
|   1       |   data      |     NULL        |       NULL       |    NULL         |
----------------------------------------------------------------------------------  
|   1       |   NULL      |     data        |       NULL       |    NULL         |
----------------------------------------------------------------------------------  
|   1       |   NULL      |     NULL        |       data       |    NULL         |
----------------------------------------------------------------------------------  
|   1       |   NULL      |     NULL        |       NULL       |    data         |
+--------------------------------------------------------------------------------+
|   2       |   data1     |     NULL        |       NULL       |    NULL         |
----------------------------------------------------------------------------------  
|   2       |   NULL      |     data1       |       NULL       |    NULL         |
----------------------------------------------------------------------------------  
|   2       |   NULL      |     NULL        |       data1      |    NULL         |
----------------------------------------------------------------------------------  
|   2       |   NULL      |     NULL        |       NULL       |    data1        |
+--------------------------------------------------------------------------------+      

I need to Receive all data in one row

+----------------------------------------------------------------------------------------+
|   f_id        |   cloumn1     |       cloumn2     |       cloumn3    |    cloumn4      |
------------------------------------------------------------------------------------------
|    1          |   data        |     data          |       data       |    data         |
------------------------------------------------------------------------------------------
|    2          |   data1       |     data1         |       data1      |    data1        |
+----------------------------------------------------------------------------------------+

Do you have a good way of writing this query?

Answer

You may use Group by and Max.

SELECT f_id,
       MAX(cloumn1) AS cloumn1,
       MAX(cloumn2) AS cloumn2,
       MAX(cloumn3) AS cloumn3,
       MAX(cloumn4) AS cloumn4
FROM   table
GROUP  BY f_id