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Thread: E-R diagram code U1

E-R diagram code U1

From
Rich Shepard
Date:
   Looking at the entity-relationship diagram for a regulatory agency database
they have attribute identifiers of PK, FKn, and U1. The first is the Primary
Key and the second is a Foreign Key, but I've not before seen a 'Un'
identifyier. I've no idea what DBMS they're using (but suspect Oracle). My
web search used in-effective terms so I could not find the answer there.

   What does U1 represent?

Rich

Re: E-R diagram code U1

From
Tom Lane
Date:
Rich Shepard <rshepard@appl-ecosys.com> writes:
>    Looking at the entity-relationship diagram for a regulatory agency database
> they have attribute identifiers of PK, FKn, and U1. The first is the Primary
> Key and the second is a Foreign Key, but I've not before seen a 'Un'
> identifyier. I've no idea what DBMS they're using (but suspect Oracle). My
> web search used in-effective terms so I could not find the answer there.

>    What does U1 represent?

Unique constraint, perhaps?  I'm just guessing.

            regards, tom lane

Re: E-R diagram code U1

From
Rich Shepard
Date:
On Sat, 29 Oct 2016, Tom Lane wrote:

>>    What does U1 represent?
>
> Unique constraint, perhaps?  I'm just guessing.

Tom,

   That's my guess, too. I've not seen it used before now and did not know if
it's a standard code for something or one specific to this agency.

Thanks,

Rich

Re: E-R diagram code U1

From
Adrian Klaver
Date:
On 10/29/2016 09:47 AM, Rich Shepard wrote:
> On Sat, 29 Oct 2016, Tom Lane wrote:
>
>>>    What does U1 represent?
>>
>> Unique constraint, perhaps?  I'm just guessing.
>
> Tom,
>
>   That's my guess, too. I've not seen it used before now and did not
> know if
> it's a standard code for something or one specific to this agency.

http://stackoverflow.com/questions/5628533/what-does-i1-i2-u1-means-in-visio-database-relationship-diagram


http://stackoverflow.com/questions/23533702/about-entity-relationship-diagram

>
> Thanks,
>
> Rich
>
>


--
Adrian Klaver
adrian.klaver@aklaver.com

Re: E-R diagram code U1

From
Rich Shepard
Date:
On Sat, 29 Oct 2016, Adrian Klaver wrote:

> http://stackoverflow.com/questions/5628533/what-does-i1-i2-u1-means-in-visio-database-relationship-diagram
> http://stackoverflow.com/questions/23533702/about-entity-relationship-diagram

   Thanks, Adrian. I suspected that I was not effectively expressing my
search terms.

Rich