Migrations Vs SQL compare tools

Brandon Casci wrote:

I'm just getting into Rails and it seems very cool so far. However I'm
having trouble understanding why Migrations are so important.

For past projects I've always used SQL comparison tools to record schema
changes, and later play them back when it's time to install a fresh DB.
It's fast, simple and it works.

On the other hand With Migrations...to me it just seems like one more
thing I have to write and one more thing that can go wrong.

What are some good reasons for me to use Migrations versus SQL scripts?

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Posted via http://www.ruby-forum.com/.

Try doing that with an 8 TB database, with a maximum allowed downtime
of 1 hour, when an entire team's salaries are measured in minutes of
downtime.

A streaming migration that maxes out both the originating and target IO
systems can just barely do it. Unload and reload via SQL scripts takes
at least 3 times as long.