DBA vs Developer in a DWH project

[mike9]

Hi everybody,

I was wondering, from your point of view or experience, what kind of task has to been done by a DBA and which one by a developer in a DWH project.

Backup Recovery is certainly a task for the DBA. But who should take care of the phisycal layout of tables/indexes? Who will take care of SQL Tuning?

Would be nice to see how the roles of the DBAs and developer are defined in your projects (specialy interested in DWH projects)

Thanks
Mike

[dknight]

Originally posted by mike9

Backup Recovery is certainly a task for the DBA. But who should take care of the phisycal layout of tables/indexes? Who will take care of SQL Tuning?

Would be nice to see how the roles of the DBAs and developer are defined in your projects (specialy interested in DWH projects)

how does your shop divide up tasks on an OLTP project? do the developers define the physical layout on an OLTP project? do the DBAs tune the code for OLTP projects? are DWH and OLTP that much different?

[SANJAY_G]

Originally posted by mike9
Who will take care of SQL Tuning?

I don't think most of the developers are capable of doing that.

[OracleDoc]

Originally posted by SANJAY_G
I don't think most of the developers are capable of doing that.

Sanjay, you are totally right. Todays developers know how to write the code(loosly stated) but most of them have no clue as to how thier code interacts with the database, let alone what an explain plan is.

Mike9, Everything you've mentioned falls under the DBA's resonsibilty. The DBA should have the say in the physical layout after all he's the one who's going to be tuning it. As I'm sure you're aware you can't just simply slap a table into the database and be done with it. It also takes an experienced DBA to know how to properly design a pyshical layout, Like ensuring tables don't get thrown into systems tablespace.

[reydp]

Is there any room for a position like a Database Architect in a DW project?

Though I haven't meet one, I'm sure the job description of a Database Architect should have a strong background of Database Administration.
I believe the more role a DBA plays in a DW project the more effective the implementation of such project.

[reydp]

OLTP inclined to response day to day user's requirements while
DWH project cater's the management(decision making) requirements.
In OLTP developers much involves in SQL tuning(if adv developer) while
in DWH projects the concentration of tuning is on the backend level. So DBA plays role importantly in DWH project.

[mike9]

Hi everybody,

Thanks a lot for all your feedback.


dknight,

are DWH and OLTP that much different

I have to admite that I have almost no experience of OLTP projects, but yes from my point of view there is a huge difference between an OLTP and a DWH. Queries against a dwh are mostly generated on the fly via a tool like Business Objects or Oracle Discoverer, in a OLTP environment I asume that most queries will be hard coded and can be well tuned. Also the amount of rows queried in a DWH is in most cases much larger as in OLTP. I a DWH you have few long runing queries in an OLTP many short queries.

[Mr.Hanky]

I think developers and DBA's (myself included) would all benefit from a 101 data modeling class. We have a team of DA (Data Analysts) that handle the model and functional design. While we do attend those meetings, the DBA's start to get involved during phyisical design.

That is when the "it's easier to code if we have one HUGE FLAT table" arguments get interesting. Anyones else been there?

MH