Re: Question about Oracle compatibility

Mario Weilguni <mweilguni(at)sime(dot)com> writes:
> In Oracle, empty strings and null are basicly the same,

Are you sure about that? It'd be a pretty major failure to comply with
SQL standard semantics, if so.

SQL92 3.1 (Definitions):

null value (null): A special value, or mark, that is used to
indicate the absence of any data value.

SQL92 4.1 (Data types)

A null value is an implementation-dependent special value that
is distinct from all non-null values of the associated data type.
There is effectively only one null value and that value is a member
of every SQL data type. There is no <literal> for a null value,
although the keyword NULL is used in some places to indicate that a
null value is desired.

There is no room there for equating NULL with an empty string. I also
read the last-quoted sentence to specifically forbid treating the
literal '' as NULL.

regards, tom lane