Re: Differences Between Oracle and SQL Server

Hello Justin,

joins, decode, other sql stuff are not the real problem for application programmer. In my last project where an application server build for Oracle has to be changed to run several databases the real problem were sequences.

MS-SQL does not have them. If you use them to create technical ids then you may run in seriuos problems.

We run in this problem because we created several objects in the application server, where some objects were connected to other object by a technical id (this id was used as primary key in the database). We created this object in the server and saved them in one step. Therefore we created the ids before we stored them. This is not supported by MS-SQL. We tried to get help from sevrels sources without real success. In the end we wrote a C++ programm that has a tcp/ip connection to the server and created the numbers for us.

A small example:

    You have a HR system with emplyees. This emplyee has an home     address. You can mapp this objects in two tables emplyee and     address where the emplyee table has a filed home_address that     contains the primary key of a record in address. When you create     a new emplyee then this emplyee has a home address object.     When saving the two objects then you first save the address copy     the id into filed home_address of the employee and save the employee.     Therefore you must create the id before you can save the emplyee.

MS-SQL has some functionality to create unique ids. Unfortenatelly this ids are created while saveing a record and the id is created in the database. You do not have direct access to it. There are methods to get this id but you have to change the logic in your server.

When asking MS-SQL guys they told me that you cannot map Oracle specifix stuff into MS-SQL server. There were other methods for application probramming but no one could tell me how to solve such a situation.

Maybe there is somebody outside that have solved this problem or has some id how to map OO application development to a relational database.

Greetings

    Clemens Hoffmann

BTW: IBM DB2 does have sequences in their server from version 7.2

"Justin Wigg" <justin_at_icsmultimedia.com.au> schrieb im Newsbeitrag news:a6k9hc$f0o7s$1_at_ID-71863.news.dfncis.de...
> "Jim Kennedy" <kennedy-family_at_attbi.com> wrote in message
> news:5Afj8.20516$702.12067_at_sccrnsc02...
> > What's your goal?
> > You could search this ng and comp.databases.oracle.server - lots of
info.
> > Which level of sql 92 standard?
> > What do you need to do? (I know you need a database, but besides that
what
> > requirements do you have?)
>
> OK - the company I work for are developing a three-tier architecture
system
> which is using a proprietary middleware language they developed. The
> database queries stored in the middleware layer are Oracle specific and
> something I have tasked myself with is finding out who to rewrite these
> queries for a SQL Server platform.
>
> Things like (as I mentioned in my first post) how do I do a left outer
join
> in SQL Server? Does SQL Server have anything that even closely resembles
> Oracle's DECODE function? What is the concatenation operator in SQL
Server?
> An on-line ready-reckoner style reference containing all this stuff is
what
> I'm after.
>
> Hope that makes some more sense...
> --
> "Managing senior programmers is | Justin Wigg - Hobart, AUSTRALIA
> like herding cats." - Dave Platt | Reply: justin_at_icsmultimedia.com.au
>
>
Received on Tue Mar 12 2002 - 02:35:21 CST