screen decoration screen decoration
Data at the heart of your organisation
Trial: £free
Standard: from £450

Merge multiple Oracle Databases into a single SQL Server Database


The Basics

SQL-Hub allows you to merge data from multiple databases into a single central view. SQL-Hub is ideal where you have more than one database containing the same types of data. SQL-Hub combines the data from the tables in each of the databases into corresponding merged tables in a central database. Each record is tagged so its source database can be easily identified.

What you need

  • SQL-Hub: you need to install the appropriate version of the SQL-Hub database integrating tool for your databases on a Windows machine
  • Connectivity: SQL-Hub needs to be installed on a machine that can connect to your source databases and the host for the central database you create
  • Permissions: you need to have a login to your database server that allows you to create the merged databases (catalogs/schemas)
  • Client Drivers: In most instances no client tools or drivers will be required however in some cases you may need to install some client software or drivers to connect to your databases - see client drivers below

Once these are in place you are ready to start...



SQL-Hub setup consists of a few simple steps...

Setting up the Central Database

  • To hold configuration information and the merged data

Connecting to a Source

  • To gather information about the structure of the source databases

Building the Central Tables

  • To create the table structure for the central copies of the chosen tables. This only needs to be done once - but can be revisited at any point

Adding Further Sources

  • To connect to each of the source databases - only the connection parameters are required, no additional configuration


  • To merge the data from all of the source databases

The Result:

  • A Central Database with a copy of the chosen tables containing the data from all of the source databases

Client Drivers

In order to connect to the Oracle source databases, either Oracle or the Oracle Instant Client - with ODBC, needs to be installed and the network configuration set up.

The Instant Client is available from Oracle - the "Basic and ODBC" packages will be required. Set the environment variable TNS_ADMIN to the path of the Instant Client Installation and install the ODBC driver by running odbc_install.exe in the Instant Client Folder

Be sure to install the correct version (32bit / 64bit) for the version of SQL-Hub you are using. There are known problems with the 64bit version of the Instant Client - we recommend sticking to 32bit.

To set up connections to the source Oracle servers you need to configure the tnsnames.ora file with entries for each server. This is well documented by Oracle but for example, the contents of this file to connect to an Oracle server with service name XE on server would be as follows

# tnsnames.ora Network Configuration File: C:\Program Files\instantclient_11_1\tnsnames.ora
# Generated by Oracle configuration tools. MAN = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = = 1521)) ) (CONNECT_DATA = (SERVICE_NAME = XE) ) )

If you are using the 32bit versions on a 64bit machine remember that you need to use the 32bit ODBC Administator (C:\Windows\SysWOW64\odbcad32.exe) if you are testing the driver.


Setting up the Central Database

  • Note: Due to limitations of the security model, if you want to use an Azure SQL Server database as the master database you will need the Azure specific version of SQL-Hub - choose "SQL Server Azure" on the download form.
  • Open SQL-Hub
  • Configure the Central Database Connection:

Enter the paramaters as follows

Central Server Name: the name of the SQL Server the merged central database is to be hosted on.
Central User Name: a SQL Server Username with access to the server and permission to create databases - if you want to use Integrated Windows Authentication enter nothing here
Central Password: the password for the SQL Server user - if you want to use Integrated Windows Authentication enter nothing here
SQL-Hub DB Name: the name for the main merged central view database
Temp DB Prefix: the prefix for central copies of the individual source databases
  • Click Connect:screendecoration

SQL-Hub will connect to the Central Server

If the connection is not succesful any errors will be shown in the progress panel.

Once the connection is made, an asterisk icon will appear.

  • Click on the asterisk to create the Central Database.screendecoration

Once the above is complete you should be able to see this database in SQL Server and you now need to connect a source database to complete the set up.

  • Click Add New Source

Now configure the first source


Connecting a Source

  • Click Add New Source
  • Configure the Source Connection:

Enter the paramaters as follows

Source Server: the name of the Oracle ODBC driver to be used (e.g. "Oracle in instantclient_11_1" - this can be found in the appropriate ODBC administrator)
Source User Name: an Oracle Username with access to the source database
Source Password: the password for the Oracle user
Source DB Name: the name of the entry for the database in the tnsnames.ora file
Source Name: the name to use for this source database in the central view
  • Click Connect:

SQL-Hub will connect to the Source Server

If the connection is not successful any errors will be shown in the errors panel.

If the Table List has not yet been created, that is the next step, if it has already been created you can proceed directly to synchronisation.

  • Click Create Table List:

You can now select the tables you want to include in your merged central database

Check the box next to each table you would like to include if this is your first time configuring a merged central view you might want to just select one or two tables to try it out. You can change the table selection later by clicking Update Table List.

  • Click Ok

Creating the central tables

SQL-Hub will display a message detailing the current status

  • Click Create Master Tables

    to create empty copies of the data tables in the merged central database

If you have not used SQL-Hub before you will need to get a FREE licence to create the master tables. To get a licence, click the Get Licence button on the licence panel, top right.

Getting a Licence

  • Click on the "Get Licence" button in the Licence panel.

    If you cannot see the Licence panel, click on the spanner icon.

  • You will be directed to the SQL-Hub website. Follow the instructions on the website

Copy and paste the code into the SQL-Hub Licence panel and click Apply.

Remember to click Create Master Tables again once you have your new licence.

Note: Some anti-virus systems (e.g. Webroot) may block the paste action on the SQL-Hub application - if you have this problem set SQL-Hub to "allow" under "Identity Protection" - feel free to switch it back to deny once you've pasted in your licence code

You are now ready to synchronise from this source

  • Click Synch


SQL-Hub allows you to synchronise in 3 ways...

On Demand Instance Synchronisation

Synchronise from a single source database from the user interface.

  • Click Synch on the panel relating to a specific source.

On Demand Full Synchronisation

Synchronise from all source databases from the user interface.

  • Click the Synch All icon on the Master Connection panel.screendecoration

Scheduled Full Synchronisation

Synchronise from all source databases from the command line automatically. See Scheduling Below

The Synchronisation Process

The synchonisation process creates a database on the central server for each instance database and creates a table in the Central database for each table included.

Data is copied from each source database to a central copy and then inserted in the merged central database table by table. The progress and any errors are displayed.

Once the process is complete you will find tables in the Central Database containing data from all of the synchronised databases and tables.



You can schedule full synchronisation using the Windows Task Scheduler

When running through the UI SQL-Hub stores connection settings in the current user profile - the same user must be used for the scheduler to allow these connection settings to be determined

  • Open the Schedule panel, below the Licence panel
  • Click "Create Task"

SQL-Hub will automatically create a task to synchronise all sources daily.

You can edit the task using Windows Task Scheduler to suit your requirements. Just find the task in the Windows Task Scheduler Library and adjust the settings.

Your SQL-Hub setup is now complete

You now have everything in place to maintain a central database containing all the data from your source databases

As we say in Manchester, Job's a good 'un

All content © SQL-Hub / Burr IST 2023
Site by Burr IST, design by foliozine

Burr Information Systems Technology Ltd

28 Park Avenue, West Point, Manchester, M19 2EE

Tel: +44 (0) 161 327 2934