I have two variables a and b in my dataset:
 a                                           b
 fd648389-7ebb-4780-b9d1-4d4d5c8656ed        NA
 9b1a0172-056a-49e2-90e0-3b73874862b0        53c9f535-dda5-4e9b-9d0a-8f8f1dc8b1fd
I want to replace variable b with a whenever b has NA
output for b:
b
fd648389-7ebb-4780-b9d1-4d4d5c8656ed 
53c9f535-dda5-4e9b-9d0a-8f8f1dc8b1fd
I tried using it but NA is replaced with 1110 instead of fd648389-7ebb-4780-b9d1-4d4d5c8656ed. Iam not sure from where is 1110 coming from.