Re: limit table to one row

g == gryzman(at)gmail(dot)com writes:

g> If you want to store period of time, why store it as varchar ?

g> just store two rows
g> create table foo(
g> n varchar,
g> val date
g> );

g> and store two rows:
g> "start", now(),
g> "end", now()+'something '::interval

g> Wouldn't that do, or is there something I misunderstand ?

Sure, that would work, but I'm having to retrofit this table to an
existing system. Much of the system I'm redesigning, but this piece
isn't too terribly important right now.

g> The approach with vertical structure, is used when people want to
g> store some particular state, say - kind of like structure in C, but in
g> SQL, and they create table for it with all the columns, etc, and have
g> to limit it to one row.

g> On the other hand, you could also use unique index on (1) approach
g> (say if you need more variety of types).

Got it.

--
Brandon