How do i update multiple rows of a table with different values in a single query??

select * from tab1;

*** Query completed. 2 rows found. 2 columns returned.
*** Total elapsed time was 1 second.

col1 col2
----------- ----------
101 vij
102 ven

UPDATE tab1
SET col2 = CASE WHEN col1 = 101 THEN 'XXXX'
WHEN col1 = 102 THEN 'YYYY'
END;

select * from tab1;
*** Query completed. 2 rows found. 2 columns returned.
*** Total elapsed time was 1 second.

col1 col2
----------- ----------
101 XXXX
102 YYYY