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On Mon, Feb 13, 2017 at 11:10 PM, Birgitta Hauser <Hauser@xxxxxxxxxxxxxxx>
wrote:

2. SQL tables never have a key (contrary to DDS described physical files).
For SQL tables AND DDS described tables primary and unique key constraints
can be defined



​My only quibble is with the above statement...​

SQL tables can and arguably must have a (primary) key; without a key, it's
not a relational table.

I understand you're trying to differentiate between a constraint and the
keyed access path of a DDS physical file.

However, a relational key is a logical component of a relational table.
The implementation details don't really matter. Besides, it's really just
a syntactical difference on the IBM i. Defining a SQL PK constraint on a
SQL tables gives you a *FILE object with a keyed access path just like
you'd get defining a unique key in the DDS for a PF.

Charles

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