Re: Understanding PostgreSQL Storage Engines

Ron Mayer <rm_pg(at)cheapcomplexdevices(dot)com> writes:
>> PostgreSQL supports and uses just only one storage engine - PostgreSQL.

> That said, ISTM one of Postgres's bigger strengths commercially seems
> to be that vendors can reasonably easily plug in different storage engines.

> Isn't the biggest SQL database in the world basically postgres using a
> non-default different storage engine[note 1 below]? Heck, companies have
> even made FPGA/hardware-accelerated storage engines for postgres[2].
> Bigger IT companies than Oracle have sold PostgreSQL using
> different storage engines[3].

> Couldn't one almost say that one of the big differences between
> MySQL and Postgres is that MySQL only offers a couple storage
> engines, while Postgres has many vendors offering engines?

Actually, that doesn't speak to storage engines at all. What that
speaks to is having a well-engineered, understandable code base that
people can modify easily. Those folk aren't "plugging in" anything,
they're just modifying what's there.

In theory one can also modify the MySQL code, but have you ever looked
at it? Man is it ugly, and AFAICT almost completely lacking in internal
documentation.

Another reason why commercial companies are forking Postgres rather
than MySQL is that our license lets them do that for free. MySQL they'd
have to pay money for (and these days, with Oracle owning the rights,
you'd be lucky if they'd allow you to sell a competing product at *any*
price).

regards, tom lane