[Twisted-Python] coding standard: plurals for database table names

[Clark C. Evans]

On Sun, Apr 06, 2003 at 02:26:13PM -0400, Steve Waterbury wrote:
| On Sun, 2003-04-06 at 13:53, Clark C. Evans wrote:
| > I noticed  in the Twisted Coding Standard that...
| > 
| >    "Database tables shall be named with plural nouns"
| > 
| > I'd like to question this standard for several reasons:
| > [ some trimming for brevity ]
| > 
| >   3. It is helpful to name foreign key columns as the
| >      same name as the table that they are coming from.
| 
| What if you have more than one foreign key to the same 
| table?  A very simple example (from my app ;^):  the 
| attributes "owner", "creator", and "modifier" all point 
| to the "persons" table.  As a rule of thumb, it's usually 
| best to name the foreign key column after the role that 
| the foreign key entity plays in the referring table.

If there is more than one role, I usually use 'role_table'
for my foreign keys.  Otherwise it gets to be a bit messy,
especially if you use inheritance of sorts (there is not
only a person table but also an employee table, etc.) in
that case, 'creator' isn't good enough in some cases, you
may mean 'employee_creator' as not all person objects 
may be possible of creating.

| >   5. While there are astechic reasons for this (above)
| >      the resons become all the more important when 
| >      you want to build automatic tools for searching 
| 
| I didn't think it was all that difficult.  I can send you
| the O-R mapping I use, if you like.

I'm not saying it isn't possible, it is just unnecessary
complexity, and to mandate this is quite irksome.

| > In short, I'd recommend singluar nouns, with M-M
| > link tables as one__two where one and two are 
| > tables being linked to.
| 
| One could reasonably argue that it is not important to have 
| a table-naming rule in the coding standard. 

That makes sense.  I'd rather no standard is better than
a bad one.  ;) Clark