How to add variables without adding cases, SPSS25

#1
I have 2 datasets.
Dataset 1 is the main file with 13000 cases (identified with the variable “id”.
Dataset 2 is the supplier file with 13400 cases and 2 variables (“id” and variable “X”). 13000 of the cases are identical to those in Dataset 1 (have the same id). 400 cases are only included in Dataset 2.
I wish to add variable “X” from dataset 2, in dataset 1. However, I do not want to add the 400 cases in Dataset 2 that are not already in dataset 1.
I have tried to add the variable “X” and this succeded, however – the 400 cases I did not want to add were added as well. How can I avoid adding the cases?
This is what I did:
I sort both files on “id”.
I stand in dataset 1, and go for “merge files”, choose dataset 2, and merge method “one to one merge based on key values”. In the variable tab, “id” is chosen as key variable and all the other variables are included. The pasted syntax looks like this:
DATASET ACTIVATE DataSet1.
SORT CASES BY id.
DATASET ACTIVATE DataSet2.
SORT CASES BY id.
DATASET ACTIVATE DataSet1.
MATCH FILES /FILE=*
/FILE='DataSet2'
/BY id.
EXECUTE.
When I run this, the variable X is added, but also the additional 400 cases.
How can I add only the variable? This was easier in the previous versions, but now the interface has changed and suddenly I cannot do this procedure correctly (although I managed this in earlier versions...)