How to compare two Oracle tables using dbForge Tools?

This tutorial describes database diff tool for Oracle table data. Read and make sure how easy you can compare Oracle tables with dbForge Data Compare for Oracle. Click the screenshots for details.

1. Opening Data Comparison Wizard

Click New Data Comparison on the Start page to launch Data Comparison Wizard. You can also start other common tasks in one click without searching a required command in the menu.

Tip: To open previous comparison projects, double-click them.

2. Selecting database connections

To create a database connection, click the New button in the wizard. The Database Connection Properties window appears. You can use either a direct or Oracle client connection.

Select the Direct check box to connect directly. Specify host, SID, port, user and password to connect to the Oracle server. Click OK to finish the creation. Now you can select this connection in the drop-down list of the Connection field on Data Comparison Wizard.

3. Selecting Source and Target for comparison

Source is the database which contents is inserted to Target after synchronization. Target is the database which contents you compare and synchronize with Source. Click the Connection fields and select required connections for Source and Target from the drop-down list.

Tip: To swap Source and Target, click the swap button. To set up custom mapping, click the Next button. To start the comparison, click Compare.

4. Selecting comparison options

You can customize comparison behavior, e.g., to ignore some objects or properties. Go to the Options wizard page and select required check boxes.

Tip: Save the comparison settings as a command line arguments file by clicking the link at the top. Later you can use this file for automatic comparison and synchronization through command line.

Tip: To save the current selection of options as your defaults, click the Save As My Defaults button.

5. Custom objects mapping

dbForge Data Compare offers both automatic and manual (custom) mapping. Use custom mapping to map tables, columns, and views that cannot be mapped automatically.

Tip: To discard custom mapping and restore to the default one, click the Reset button.

Mapping tables and views

Map tables and views with a different data structure manually in several clicks.

Click the Map Objects button and select Source and Target objects in the open window, then click OK. The selected pair of objects will appear in the grid on the Mapping wizard page and be compared.

Tip: To map multiple pairs of Source and Target objects without closing and opening the window many times, click the Map button after the first selected pair of objects. When you manually select all required objects, click OK to see them in the grid on the Mapping wizard page.

Mapping columns

See how many columns of each object can be compared in the Columns in Comparison field of the grid.

Click the ellipsis button for the required object. The open window will show all the columns (and their details) of the selected object.

Automatically mapped columns are marked with the green icon. Incompatible columns are marked with the red icon. Select required Target columns from the drop-down list and click OK.

Mapping custom queries

Map the results of custom queries.

Click the Custom Query button and write the needed queries for Source and Target in the corresponding SQL fields. You can select to map query result with a table. Click Map to perform mapping and OK to close the window.

Tip: To validate queries, click the Validate button or select the Validate item from the context menu in the needed SQL field.

6. Analyzing comparison results

See the full info about compared objects in the data comparison document. The top grid shows all the compared objects. The bottom grid shows the records of the selected object, automatically grouped by status - Identical, Different, Only in Source, and Only in Target.

Select required objects or separate records of objects to synchronize.

Tip: For better understanding, filter the objects in the top grid, e.g., to see Only in Source objects.

7. Synchronizing data

Use Data Synchronization Wizard to generate a standards-driven synchronization script and tune the synchronization result based on your needs. Click the Synchronize button to immediately generate the synchronization script.

Tip: To customize synchronization, click Next and move to other wizard pages.

On the Options wizard page, customize the synchronization by applying various options.

To see the synchronization actions and the list of warnings generated during mapping, move to the Summary wizard page.

On the Summary wizard page, check the synchronization action plan and the list of warnings generated during mapping.

After Data Synchronization Wizard work is completed, the synchronization script will be opened. Click the Execute button on the toolbar to execute it.

8. SQL script management

Use SQL editor to view and edit synchronization scripts, create queries and execute them against the selected database.

Click the New SQL button to open SQL editor.

Tip: When the query is executed, see the query results in the Data window that opens. Find rich data management options in the right-click menu.


This tutorial has shown how you can easily compare data in Oracle tables and see differences. Go through individual records or group them together. Create errorless SQL scripts to deploy data modifications between your environments.