Re: Reality check on PFs created as SQL TABLEs

Of course you can:

	CONSTRAINT "XXXX_PK" PRIMARY KEY (field1, field2)

But it's somehow "deprecated" to use a multi-column primary key.

Today an automatic ID column should be the primary key - all other key, especially multi-column keys, are normally done as indexes.

HTH
Daniel


> Am 10.06.2026 um 20:12 schrieb James H. H. Lampert via MIDRANGE-L <[email protected]>:
> 
> On 6/10/26 10:43 AM, Daniel Gross wrote:
>> Yes - primary key constraint is the way - the primary key "index" is
>> embedded in the table/PF object.
> 
> Thanks. That worked, and the syntax is correct.
> 
> I could have sworn that you couldn't have keyed SQL tables . . . and I just found the exact same constraint clause in *SQL for Dummies,* after having created a test table using the clause.
> 
> I don't suppose it's possible to create an SQL TABLE with more than one inherent keyfield, the way you can with a DDS-defined PF, is there?
> 
>> On 6/10/26 10:51 AM, Dan Bale wrote:
>> If I'm not sure how SQL "replicates" a DDS feature, I'll use the Generate SQL function in Run SQL Scripts to generate the converted
>> SQL source for DDS PF & LF objects.
> I tried an experiment. With PF "FOO" generated from the following DDS:
> 
>    A          R FOOBAR
>    A            FIELD1        10A
>    A            FIELD2        10A
>    A          K FIELD1
>    A          K FIELD2
> 
> I tried "Generate SQL," and got:
> 
>  CREATE TABLE MERCURY.FOO (
>  --  SQL150B   10   REUSEDLT(*NO) in table FOO in MERCURY ignored.
>  --  SQL1506   30   Key or attribute for FOO in MERCURY ignored.
>    FIELD1 CHAR(10) CCSID 37 NOT NULL DEFAULT '' ,
>    FIELD2 CHAR(10) CCSID 37 NOT NULL DEFAULT '' )
>    
>    RCDFMT FOOBAR     ;
> 
> So it looks like "anything DDS PFs & LFs support, SQL does as well" is indeed an oversimplification.
> 
> Then again, Theory and practice are the same in theory, but not necessarily in practice. (Paraphrased from a maxim falsely attributed to Yogi Berra, among others, that may have originated with Jan van de Snepscheut.)
> 
> --
> JHHL
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