Re: Advanced SQL

Quoth Evan Keel:
"David Portas" <REMOVE_BEFORE_REPLYING_dportas@xxxxxxx> wrote in message
news:pZSdnfih_oRy5H3bRVnyigA@xxxxxxxxxxxxxxx
Call me picky but I am not entirely comfortable with that U.Texas site,
even though it's a commendable effort overall.

"The definition of second normal form states that only tables with
composite primary keys can be in 1NF but not in 2NF"

They have it right here. All non-key attributes must be dependent on the
full key. Only applies to tables with keys composed of multiple columns>

No. There may be dependencies where the left side is empty. But it's a
common mistake. If I remember correctly, one of my database textbooks
"proves" that any relvar with just two attributes is automatically in BCNF.
--
Jon
.

Relevant Pages

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  • Re: Advanced SQL
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