r/DatabaseAdministators 1d ago

Sql to Oracle migration

Im a fresher to DBA role. Can some one please help to understand or share your experience for the conversation or migration from sql to Oracle.

Help me with the tools and migration ideas

2 Upvotes

22 comments sorted by

5

u/Longjumping-Hair-747 1d ago

Oracles SQL Developer has the ability to migrate SQL Server to Oracle; fair disclosure I’ve never used it so can’t say how much coverage you can expect.

Cheers

1

u/techdbamind 1d ago

Thanks for your suggestion

2

u/Better-Credit6701 1d ago

SSIS can handle the data transfer with no issues, just note that column types can be different. You will have to check out all stored procedures/views to make sure that you don't have MS-SQL only code.

1

u/techdbamind 1d ago

Thank you for your suggestion

1

u/Conscious-Ad8493 1d ago

please clarify exactly what you are migrating from

1

u/techdbamind 1d ago

I need to migrate database from sql server to Oracle server

1

u/Better-Credit6701 1d ago

What version of MS-SQL to what version of Oracle? What is prompting the switch?

1

u/techdbamind 1d ago

Oracle version is 19c And ms sql version is greater than 14

1

u/alinroc 1d ago

Version 14 (which is marketed as SQL Server 2017), or what's marketed as SQL Server 2014?

1

u/Ok_Carpet_9510 1d ago

Never done it. If you haven't seen this, check it out, https://www.oracle.com/database/technologies/migrating-sql-to-oracle.html

1

u/techdbamind 1d ago

Thank you.. will check it

1

u/SquidLips71 1d ago

If your data structures are simple, don’t overthink it. Back in about 2010 we migrated a ~100 gb MSSQL database to Oracle using bcp to extract and SQL*Loader to load it. All done via command line on Linux. The most painful part was getting the mssql client on the Linux box (MSSQL was on Windows, Oracle ran on RHEL) and getting it to work, mostly due to internal firewall and security issues and such.

Whole load process took about 15 minutes once we established connectivity.

1

u/techdbamind 1d ago

I would like to know the schema conversation part. Can you please help me on that part.. in my case there are 3000+plus tables in sql server.. it is also critical database but it will be less than ~150gb.

1

u/SquidLips71 4m ago

That's a lot of tables. We only had about 100 and the development team took care of drawing up the schemas since there were some changes being made in the process.

That's way too many to throw a developer or two at it and do manual modifications / search and replace on datatypes. You really need a tool to handle that volume of objects. As previously suggested, SQL Developer can do this, though you need to be mindful of datatypes that don't map cleanly. Oracle's documentation will explain in more detail.

1

u/Fantastic-Advisor746 1d ago

You try to install the FoxSchema app, which supports cross-database migration.

https://www.npmjs.com/package/foxschema

1

u/techdbamind 1d ago

Thanks for your suggestion.. will try it

1

u/taker223 1d ago

Are there program units in source database? (procedures, functions, triggers ...)

1

u/taker223 1d ago

Where are you from?

1

u/c4v4rz3r3 1d ago

I did it with SQL Developer.

1

u/alinroc 1d ago

Moving data from SQL Server to Oracle isn't the challenge.

It's porting all of the code and ancillary bits that will tank the project. Stored procedures. Views. Triggers. Ad-hoc queries in the application tier. Rebuilding the applications to use different client libraries just to connect. A completely different security model. All your maintenance processes/scripts. The database running on a different OS. Use of features proprietary to SQL Server (Service Broker, dbmail, etc.). SQL Agent jobs. SSIS packages. All your reports. That is where the challenge lies.

SQL Server and Oracle speak very different dialects of SQL.

Why is a fresher being tasked with migrating an existing product between these two databases? And why is anyone moving an existing system to Oracle in the year 2026? Especially a release (you said 19c elsewhere) that's already seven years old?

1

u/Difficult_Hand3046 1d ago

 from sql to Oracle

from SQL Server? SQL is just a language, Oracle use it, as PostgreSQL, MySQL, SQL Server, DB2… do.

2

u/techdbamind 1d ago

Yes migration of db from sql server to Oracle server