DHH Interviewed by MySQL


#1

I didn’t see anyone post a link to David’s Interview by Lenz here on the
list so I decided to post it.

The interview can be accessed here:
http://dev.mysql.com/tech-resources/interviews/david-heinemeier-hansson-rails.html

I was very happy to see the interview on PlanetMySQL as just the other
day I was talking about RubyOnRails on my MySQL blog which is
syndicated on PlanetMySQL
(http://mysqldatabaseadministration.blogspot.com/2006/01/what-is-your-programming-language-of.html)
and was surprised to see that no one posted a comment about Rails.

I am also very glad to hear about DHH’s future plans of continuing to
support Rails but not like MySQL AB supports MySQL

On the other hand, being a DBA, I was kinda disappointed at David’s
following remarks:

“I love MySQL because its fast and easy for the simple stuff. IÂ?m
entirely uninterested in fancy features like stored procedures,
triggers, and the like. So I hope nothing is being sacrificed while the
5.0 series chases these. My advice would be to focus on enabling that
simple feature set to go higher. Make clustering and other scaling
techniques even easier. Perhaps baking in support for managing
partitioned data sets.”

I think stored procedures, triggers and events are very needed in
MySQL. Hope David is not worried about competition from MySQL :slight_smile:

MySQL users, I would love to hear your opinions on the above
statement.

Frank


#2

softwareengineer 99 wrote:

On the other hand, being a DBA, I was kinda disappointed at David’s
following remarks:

“I love MySQL because its fast and easy for the simple stuff. IÂ?m
entirely uninterested in fancy features like stored procedures,
triggers, and the like. So I hope nothing is being sacrificed while the
5.0 series chases these. My advice would be to focus on enabling that
simple feature set to go higher. Make clustering and other scaling
techniques even easier. Perhaps baking in support for managing
partitioned data sets.”

I think stored procedures, triggers and events are very needed in
MySQL. Hope David is not worried about competition from MySQL :slight_smile:

MySQL users, I would love to hear your opinions on the above
statement.

I think it’s more along the lines of keeping everything in one layer.
See this:

Choose a single layer of cleverness
http://www.loudthinking.com/arc/000516.html

I’m sort of coming around to that way of thinking. I switched from MySQL
to PostgreSQL about two years ago and loved it. But now it DOES sound
appealing to just handle stuff in Ruby/Rails instead of switching to
pgsql for sprocs, constraints, triggers, etc. and then handling db
errors that arise from them.

Joe


#3

On 2/10/06, Joe removed_email_address@domain.invalid wrote:

I’m sort of coming around to that way of thinking. I switched from MySQL
to PostgreSQL about two years ago and loved it. But now it DOES sound
appealing to just handle stuff in Ruby/Rails instead of switching to
pgsql for sprocs, constraints, triggers, etc. and then handling db
errors that arise from them.

This is one case where I have no problem being unDRY. The fact is
that for the apps I write, my Rails app isn’t going to be the only
point of access to the DB. Most of the time the DB is there long
before the Rails app anyway. So there are two ways of handling things
that need checks, in my mind:

  1. Write code to handle errors that pop up from the DB
  2. Code the checks into the application itself

Sometimes it’s easier and makes more sense to do #1. In Rails, you
can achieve nearly all of the checks with one line of code, and
everything else with just a few. You never even get to a point where
the database would create errors.

Anyway this is getting slightly OT. Basically I just mean that I’ve
got no problem having two layers of cleverness. It’s necessary for me
to have a clever database, and easy for me to have a clever Rails app.
The Rails app never sees the DB cleverness, which only exists because
other languages and people that access the DB aren’t as bright.

Pat


#4

Pat M. wrote:

On 2/10/06, Joe removed_email_address@domain.invalid wrote:

I’m sort of coming around to that way of thinking. I switched from MySQL
to PostgreSQL about two years ago and loved it. But now it DOES sound
appealing to just handle stuff in Ruby/Rails instead of switching to
pgsql for sprocs, constraints, triggers, etc. and then handling db
errors that arise from them.

This is one case where I have no problem being unDRY. The fact is
that for the apps I write, my Rails app isn’t going to be the only
point of access to the DB. Most of the time the DB is there long
before the Rails app anyway. So there are two ways of handling things
that need checks, in my mind:

  1. Write code to handle errors that pop up from the DB
  2. Code the checks into the application itself

Sometimes it’s easier and makes more sense to do #1. In Rails, you
can achieve nearly all of the checks with one line of code, and
everything else with just a few. You never even get to a point where
the database would create errors.

Anyway this is getting slightly OT. Basically I just mean that I’ve
got no problem having two layers of cleverness. It’s necessary for me
to have a clever database, and easy for me to have a clever Rails app.
The Rails app never sees the DB cleverness, which only exists because
other languages and people that access the DB aren’t as bright.

Pat

Yeah, I’m redundant in this too. I’ve started using runner scripts more
to interact with models, but I still do a lot of interfacing via psql
and phppgadmin and not having data integrity protections in place at
that level would be playing with fire. They haven’t interfered with
Rails or gotten in the way - things like validates_uniqueness_of happen
before a unique key in postgresql can generate an error.

Joe


#5

Thank you Pat and Joe for your comments.

As far as my thoughts are concerned, MySQL needs SP and triggers so it
won’t loose DBAs to PostgreSQL.

I asked the same question on my MySQL blog
(http://mysqldatabaseadministration.blogspot.com/2006/02/entirely-uninterested-in-fancy.html)
to database administrators and got some very interesting replies:

Markus, a recognized MySQL DBA put the opinions of many MySQL DBA’s in
excellent words on his site:
http://db4free.blogspot.com/2006/02/entirely-uninterested-in-fancy.html

I present a quote from above:

"MySQL simply needs features like Stored Procedures, User Defined
Functions, Triggers etc. to be taken serious on the database market! So
long has MySQL been criticized for not providing them - now as they
have been introduced, it would be stupid to criticize MySQL for
providing them.

MySQL has a very good chance to get as advanced as any other database
system without losing it’s simplicity. I don’t think that performence
will suffer a lot in the long run, because performence optimizations
will certainly go on forever and will certainly overcome the speed
decreases that may come from implementing new features. On the other
hand, the other database systems will hardly ever have a chance to
become as convenient to work with as MySQL (of course, people will
always like what they are used to - if somebody has always worked with
another product, he’ll be more comfortable with this than with another

  • but for new users, MySQL is probably less painful to start with than
    the others).

    The great thing is - people can still work with MySQL 5.0 the way
    that they were used to with earlier versions. They can decide whether
    to use the new features, or not. And that’s exactly the right way for
    MySQL! Continuing to get as advanced as possible without breaking
    downward compatibility - where possible (and useful)."

    Another anonymous commenter said that if it wasn’t for the SP and
    triggers he wouldn’t have converted from MSSQL to MySQL.

    While Rails is a wonderful framework, and Ruby an excellent language,
    I believe there is a strong need for these features. Somethings are
    just better left to the database. For example, I can think of many
    situations, where the DRY can be applied in a better way by using
    triggers.

    – Frank

Pat M. removed_email_address@domain.invalid wrote: On 2/10/06, Joe wrote:

I’m sort of coming around to that way of thinking. I switched from MySQL
to PostgreSQL about two years ago and loved it. But now it DOES sound
appealing to just handle stuff in Ruby/Rails instead of switching to
pgsql for sprocs, constraints, triggers, etc. and then handling db
errors that arise from them.

This is one case where I have no problem being unDRY. The fact is
that for the apps I write, my Rails app isn’t going to be the only
point of access to the DB. Most of the time the DB is there long
before the Rails app anyway. So there are two ways of handling things
that need checks, in my mind:

  1. Write code to handle errors that pop up from the DB
  2. Code the checks into the application itself

Sometimes it’s easier and makes more sense to do #1. In Rails, you
can achieve nearly all of the checks with one line of code, and
everything else with just a few. You never even get to a point where
the database would create errors.

Anyway this is getting slightly OT. Basically I just mean that I’ve
got no problem having two layers of cleverness. It’s necessary for me
to have a clever database, and easy for me to have a clever Rails app.
The Rails app never sees the DB cleverness, which only exists because
other languages and people that access the DB aren’t as bright.

Pat


#6

On 11/02/06, softwareengineer 99 removed_email_address@domain.invalid wrote:

I think stored procedures, triggers and events are very needed in MySQL.

But the interview was about what DHH thinks, not you :slight_smile:
He’s said several times before that Rails prefers an ‘application
database’ to an
‘integration database’, and he prefers to put that checking in the
model rather than
the db.

I suspect most mysql users don’t need those features, or they
wouldn’t be mysql users.


Rasputin :: Jack of All Trades - Master of Nuns
http://number9.hellooperator.net/


#7

A few more negatives for me against MySQL are:

  • its licensing (which is confusing - even their reps couldn’t explain
    it).
  • its deviance from SQL conformance (which every database has, but
    MySQL’s is much more so).
  • its confusing array of database engines (and the uncertainty of InnoDB
    since Oracle’s acquisition).
  • its worse performance (for me anyway) due to table locking issues, and
    tables getting corrupted/wedged from time to time.

MySQL can do whatever they want ;). I don’t anticipate ever going back
as a developer. But choice and competition are good :).

Joe