VARCHAR variable in where clause

Hi NG

How do I have to use a VARCHAR2 variable in a where clause. I could not find an example.

PART NR VARCHAR2(20);
myPartId NUMBER()20;

PART NR := '101 189';
select part id into myPartId from part where part nr = PART NR; -- not working, hwo to do ?

How do I have to "escape" the PART NR, that it will be:

where part nr = '101 189'

Thanks
Peter

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