Eric M Russell (12/17/2014)
DonlSimpson (12/17/2014)
As a side note, on some RDMS platforms, various stubbed values are treated literally as NULL. For example, Oracle treats an empty string as NULL.What this means is that ...
'' is null : TRUE
'Smith' > '' : FALSE
'' = '' : FALSE
I discovered that the hard way when working on a project that exchanged data between SQL Server and Oracle.
Oracle does have an interesting concept of null. Thus all of these return 'ac':
select replace('abc','b','') from dual;
select replace('abc','b',null) from dual;
select 'a'||null||'c' from dual;
But this returns null:
select 1+null+3 from dual;