RE: Migration from SQL Server to Oracle database

From: <>
Date: Mon, 14 Nov 2011 08:58:21 -0500
Message-ID: <>

You might consider Expert Oracle Database Architecture by Thomas Kyte. Not sure if he has an 11g version out yet, but he clearly explains differences such that the databases don't just 'switch' databases --- or rather you 'can' move the data, but the applications need a lot of attention.

For instance, the locking mechanisms operate differently. Essentially you want to take advantage of the database housing the data -- otherwise one might be surprised to hear that it is not running 'faster'. The reason would be that one is trying sql server stuff on the oracle DB.

Joel Patterson
Database Administrator
904 727-2546

-----Original Message-----
From: [] On Behalf Of Krishna Sent: Saturday, November 12, 2011 4:17 PM To: Martin Berger
Subject: Re: Migration from SQL Server to Oracle database

we need to convert sql server databases only once to oracle. I understand that, even though we use once for initial data loads, we need to pay the license for all cores in oracle database. same thing for gateways... Am I right ?
Once we migrate to oracle, the sql server database servers will be decommissioned.

Martin, I understand that I need to change data types for cols. sql server databases will become schemas in oracle. Should I make any other physical design changes?

On Sat, Nov 12, 2011 at 1:55 AM, Martin Berger <>wrote:

> Krishna,
> have you ever thought about Transparent Gateway? [1]
> I would try to do the DDLs via any tool like SQLDeveloper - probably they
> can use some hand-made modifications. As SQL Server differs from Oracle in
> features and weaknesses, it's worth to think about changes of physical
> parameters of the objects.
> hth
> Martin
> [1]
> On Sat, Nov 12, 2011 at 03:34, Krishna <> wrote:
>> I have got 2 questions:
>> 1. We are planning to convert our OLTP sql server databases to oracle
>> databases. I tried using SQL Developer to migrate a small sql server
>> database to oracle database(size 5Gb). It was fine. when I tried to
>> migrate
>> another database(size 90G), it is taking too long. The problem with sql
>> developer is I cannot choose and pick tables. out of 250 tables, I need to
>> migrate abt 80 tables(size will be abt 50G). can anybody share their
>> experiences, if any, in converting medium size sql server databases to
>> oracle databases? any others options??
>> 2. I am planning to convert sql server ddl to oracle ddl. I am testing bcp
>> out and use sql loader to import the data. Right now, I am manually
>> creating oracle tables from sql server tables. I am using
>> to
>> convert the code. Are there any other better ways to convert sql server
>> DDL to Oracle DDL?
>> Thanks in advance
>> krishna
>> --


Received on Mon Nov 14 2011 - 07:58:21 CST

Original text of this message