Re: 4 the FAQ: Are Commercial DBMS Truly Relational?

NO!

SQL NO! End of debate. (vbg)

Check out www.dbdebunk.com

--
Slainte

Craig Alexander Morrison


"Kenneth Downs" <firstinit.lastname_at_lastnameplusfam.net> wrote in message
news:hqd6kc.4go.ln_at_mercury.downsfam.net...


> It said often here that no commercially available DBMS is truly

relational,


> but I haven't seen a succinct list of reasons.  What are they?

>

> One that I have gleaned from lurking is that the DBMS's allow duplicates,

as


> in:

>

> CREATE TABLE AnyTable (col1 char(1), col2 char(1), col3 char(1));

> INSERT INTO AnyTable (col1,col2,col3) VALUES ('A','B','C');

> INSERT INTO AnyTable (col1,col2,col3) VALUES ('A','B','C');

>

> The table create specifies no constraints, and so the next two insert

> statements are both allowed.  The objection to this seems to be that the

> RDM requires an implied unique constraint on all columns of all tables.

> Because such a constraint is not present, they are not truly relational.

>

> Is that right?

>

> What are some of the other objections?

>

> We could probably have the same discussion re: Structured Query Language

is


> not relational.

>

> --

> Kenneth Downs

> Use first initial plus last name at last name plus literal "fam.net" to

> email me