Naming of ID columns in database tables

Question

I was wondering peoples opinions on the naming of ID columns in database tables.

If I have a table called Invoices with a primary key of an identity column I would c

Answer 1

Coming at this from the perspective of a formal data dictionary, I would name the data element invoice_ID. Generally, a data element name will be unique in the data dictionary and ideally will have the same name throughout, though sometimes additional qualifying terms may be required based on context e.g. the data element named employee_ID could be used twice in the org chart and therefore qualified as supervisor_employee_ID and subordinate_employee_ID respectively.

Obviously, naming conventions are subjective and a matter of style. I've find ISO/IEC 11179 guidelines to be a useful starting point.

For the DBMS, I see tables as collections of entites (except those that only ever contain one row e.g. cofig table, table of constants, etc) e.g. the table where my employee_ID is the key would be named Personnel. So straight away the TableNameID convention doesn't work for me.

I've seen the TableName.ID=PK TableNameID=FK style used on large data models and have to say I find it slightly confusing: I much prefer an identifier's name be the same throughout i.e. does not change name based on which table it happens to appear in. Something to note is the aforementioned style seems to be used in the shops which add an IDENTITY (auto-increment) column to every table while shunning natural and compound keys in foreign keys. Those shops tend not to have formal data dictionaries nor build from data models. Again, this is merely a question of style and one to which I don't personally subscribe. So ultimately, it's not for me.

All that said, I can see a case for sometimes dropping the qualifier from the column name when the table's name provides a context for doing so e.g. the element named employee_last_name may become simply last_name in the Personnel table. The rationale here is that the domain is 'people's last names' and is more likely to be UNIONed with last_name columns from other tables rather than be used as a foreign key in another table, but then again... I might just change my mind, sometimes you can never tell. That's the thing: data modelling is part art, part science.