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Each Dimension Data Validation report contains information about the levels of one or more dimensions. Each report may also contain warning or error messages. The All Messages report contains the messages generated for all of the reports that have been run.
If a report has no messages, then the report encountered no error or warning conditions. Most of the descriptions of the messages contain suggestions on how to correct the problem.
A warning message indicates that the dimension may be maintained and that data is consistent within the cube, but that some of the data might cause unexpected results when reporting data. For example, a warning message might indicate that a dimension member has more than one value for a descriptive label.
An error message indicates a condition that might cause problems when maintaining the dimension or that might produce unexpected results within the cube. For example, having dimension members with different parent values in different rows of the dimension table is reported as an error because data could aggregate in ways that could be unexpected by the user.
You should resolve errors messages before maintaining the dimension. You should consider warning messages in the context of the tools with which users query the OLAP cube. For example, certain applications might be able to query a ragged (uneven) hierarchy and other applications might not.
For most rows in a report, you can view the SQL statement that Dimension Data Validation uses to get the data for that row. You can also view details about the row. The details usually include relevant data from the source table and methods for correcting the problems.
From the details dialog box you can view the SQL statement that generates the data for the level. When a data correction method is available, you can view the SQL statement for the fix. You can export the SQL to the clipboard or to the SQL Developer worksheet.
You can then run the SQL for the fix. You can return to Dimension Data Validation, run the report again, and view the results. If the results are satisfactory, you can commit the changes in SQL Developer or the other application you are using.
You can refresh the data displayed in the details dialog box at any time.
The following topics describe how to run Dimension Data Validation reports.
The following procedure describes the first steps in using Dimension Data Validation.
To start Dimension Data Validation and view mappings:
In the SQL Developer Connectors navigator, expand OLAP Option and then Analytic Workspaces. Right-click an analytic workspace and select Dimension Data Validation.
The Launching Dimension Data Validation dialog box appears and reports the progress of the validation process. To stop the operation, click Cancel Task; otherwise, the Dimension Data Validation for Analytic Workspace analytic_workspace_name dialog box appears.
The dialog box contains a navigation tree, which lists the reports that you can generate, and a pane that displays the selected report, which is initially the All Messages report. If this is the first time you have used Dimension Data Validation, then the rows in the All Messages report are empty.
In the navigation tree, click Metadata and Mappings.
The Metadata and Mappings tab displays the status of the mappings of the dimension metadata to the source tables in the database. It reports errors detected in the mappings. If an error exists, do the following:
Using the OLAP option, correct any errors in the mappings of the dimensions in the analytic workspace.
Exit Dimension Data Validation and restart it.
Repeat these Step 2 until no mapping errors are reported.
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See Also:
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Before running all reports for all dimensions, see the following note.
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Note: While most reports run very quickly even on large dimensions, the Duplicate Members across Levels report might take a considerable amount of time to run on large dimensions because it compares members in every level with members of every other level. A large table with many levels takes considerably longer to test as compared to a small table with few levels. If your dimension table is very large, then considering running individual reports as needed rather than running all reports.To prevent this report from running when you run the All Members Report, you can disable this report by right-clicking Duplicate Members across Levels in the navigation tree and selecting Disable Duplicate Members across Levels Report. |
To run all reports for all dimensions, do the following.
Right-click All Messages in the navigation tree.
Point to Validate.
Select All Dimensions.
To run all reports for a specific dimension, do the following.
Right-click All Messages in the navigation tree.
Point to Validate.
Select a dimension.
To run data validation for a specific report for all dimensions, do the following.
Right-click the report in the navigation tree.
Point to Validate Report for.
Select All Dimensions.
To run data validation for a specific report for a specific dimension, do the following.
Right-click the report in the navigation tree.
Point to Validate Report for.
Select the dimension.
You can view the SQL statement that generates the data in the rows of a report.
To view the SQL for a row in a report:
Select a row in the report.
Click Show SQL.
The content of the details for a row in a report varies with the parent report. Some details are simply informative, for example the details for a row in the Distinct Members report shows the dimension members at the selected level. Other details display problematic data and provide methods that you can use to fix some of the problems.
You can view the SQL statement that generates the data for the details. For most reports, you can use one of the data correction methods to fix the reported problem.
To view the details for a row in a report:
Select a row in the report.
Click Details.
From the details dialog box you can click Show Detail SQL to view the SQL statement that generates the data for the level.
When a data correction method is available, the SQL statement for the fix appears in the field below the options. You can click export the SQL statement to the clipboard or to the SQL Developer worksheet.
You can then run the SQL for the fix in SQL Developer or an application such as SQL*Plus. You can return to Dimension Data Validation, refresh the metadata, and view the results.
By using the data correction methods, you can quickly change the data in dimension tables during the proof of concept or early design stage of the OLAP cube design process. Correction methods provided by Dimension Data Validation are not a substitute for a high-quality extraction, load, and transform process in the data warehouse or for data quality tools.
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Note: Be aware that if you change dimension members at the lowest (leaf) levels of a dimension table, then you might also have to change keys in the fact table. |
The Details for report at Level level_name in hierarchy dialog box displays the SQL statements that the plug-in executes for the selected correction method. You can export the SQL statement it to a SQL Developer Worksheet or to the clipboard and paste it into a tool such as SQL*Plus. You can then execute the SQL or you can modify it as desired before executing it.
In some cases the data correction method tests whether a column is wide enough to accommodate the updated values and generates an ALTER TABLE statement to increase the column width if necessary.
Although the data correction methods vary for each report, the general procedure for using the methods is the same for all reports.
From the summary report, select a row in the table and click Details.
In the Details for Report at Level LEVEL_NAME in HIERARCHY dialog box, select a data correction method and supply the required or optional information.
The SQL statement for the correction method appears in the field below the options.
To export the SQL statement for the correction method, click Export.
To export the SQL statement to a SQL Developer Worksheet, click To Worksheet.
To export the SQL to the clipboard, click To Clipboard.
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Tip: If you export to the Worksheet, then you may want to close the details dialog box and exit the Dimension Data Validation extension so that the Worksheet is more readily visible.If you start the Dimension Data Validation extension in the same SQL Developer session, then it returns you to the report that you were viewing. |
Execute the SQL.
Run data validation reports again for the affected dimension.
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Note: Because changing data in a dimension table often affects multiple reports, you should run all reports for a dimension after changing data. |
(Optional) To make the data changes permanent, commit the transaction in SQL Developer or the tool you are using.