Question

Can someone help me with the below query in oracle?
The logic is that if the person has a friendlyname , use that for match with the ‘search’ criterion. Else, try to match with the realname column.

select * from people where   
case when customer_friendlyname is null then realname like '%abcd%'  
else   
case when customer_friendlyname is not null then customer_friendlyname like '%abcd%'  
end   
end  

Appreciated if someone could take a look.. Thank you!

Answer 1

In Oracle, Boolean expressions can’t be treated like other types of expressions; for example, CASE expressions can’t evaluate to them. So you need to rewrite this.

In this case, since you have the same LIKE '%abcd%' predicate in both branches, you could just factor it out:

WHERE ( CASE WHEN customer_friendlyname IS NULL
             THEN realname
             ELSE customer_friendlyname
         END
      ) LIKE '%abcd%'

but it’s simpler to make use of the built-in NVL function, and write:

WHERE NVL(customer_friendlyname, realname) LIKE '%abcd%'