I have a big data set with a column name "CORINE" with strings in it. I want to change these individuals strings into integers and put it into a new column, so that i can create a raster layer out of the created values. 
I tried this code in the field calculator.

```
CASE 
  WHEN "CORINE" = "AG" 
  THEN 1
  WHEN "CORINE" = "BG" 
  THEN 2
  WHEN "CORINE" = "LW" 
  THEN 3
  WHEN "CORINE" = "NW" 
  THEN 4
  WHEN "CORINE" = "MW" 
  THEN 5
  WHEN "CORINE" = "WW" 
  THEN 6
  WHEN "CORINE" = "WA" 
  THEN 7
  WHEN "CORINE" = "DK" 
  THEN 8
  WHEN "CORINE" = "LN" 
  THEN 9
  WHEN "CORINE" = "NV" 
  THEN 11
  WHEN "CORINE" = "SU" 
  THEN 12
  WHEN "CORINE" = "SV" 
  THEN 13
  WHEN "CORINE" = "TM" 
  THEN 14  
  ELSE 0
END
```

But after the calculations all the values in the new column are 0. 
What is my mistake?

[![enter image description here][1]][1]


  [1]: https://i.sstatic.net/MJFsN.png