The following limitations and known issues apply to Data Virtualization.
Governing data
- Access control issues when you preview assets with masked or filtered data
- Automatic publishing of virtual objects to the catalog is limited to certain objects
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Only objects that are created in the user interface are automatically published to the catalog. Objects that are created using SQL are not published automatically and must be published to the catalog manually or by using the API.
- Cannot see column business terms for virtual object
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You are virtualizing a table in Data Virtualization and you want to see the list of business term assignments on the Virtualize page. However, in the default virtualization mode, you cannot see any column term assignments; and in the strict virtualization mode, you cannot see table A on the Virtualize page.
You might encounter this issue when column business terms are assigned multiple times in a governed catalog. For example, you add a data asset for table A with its table and column term assignments in a governed catalog. Then, in the same governed catalog, you add a data asset for the same table A with its table and column term assignments. As a result, you might encounter this issue in Data Virtualization.
To avoid this issue in the default virtualization mode, don't assign column business terms multiple times in a governed catalog.
- Access to a table is denied by policies
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You cannot access a table but according to the data policies and authorizations, you are authorized to access this table. This issue occurs only if IBM Knowledge Catalog policy enforcement is enabled in Data Virtualization.
To solve this issue, see Access to a table is denied by policies in Data Virtualization.
- Do not use duplicate assets for the same table
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The policy service is unable to decide which of the duplicated assets to use for policy enforcement and does not aggregate the rules. You must avoid duplicate assets across governed catalogs as this might lead to issues with policy enforcement behavior in Data Virtualization.
- Cannot access assets in the catalog
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When you try to access Data Virtualization assets in IBM Knowledge Catalog, the access is denied.
To solve this issue, see Cannot access assets in the catalog in Data Virtualization.
- Cannot enforce policies and data protection rules
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You enabled policy enforcement but policies and data protection rules are not being enforced in Data Virtualization.
To solve this issue, see Cannot enforce policies and data protection rules in Data Virtualization.
- Profiling of data assets in Data Virtualization fails
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When you try to profile catalog assets from Data Virtualization in IBM Knowledge Catalog, you might see a SCAPIException:CDICO0103E message. You are not authorized and the message indicates Connection authorization failure occurred.
Ensure that all prerequisite setup steps are completed to authorize the IBM Knowledge Catalog service to access data in your Data Virtualization instance. See Profiling catalog assets fails with SCAPIException: CDICO0103E message in Data Virtualization.
- Cannot publish data to data science notebooks in Watson Studio
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Publishing data to data science notebooks in Watson Studio is not supported.
Data sources
- Japanese column names are not displayed correctly
- When you virtualize JSON files with Japanese data on IBM® Cloud Object Storage, the Japanese column names might be translated to
hex values. The
allownonalphanumeric
option can be used to resolve this issue. However, theallownonalphanumeric
option is disabled by default and you must contact IBM® Cloud support to open a ticket to have the option enabled.
- Cannot connect to Generic S3 or Microsoft Azure Data Lake Storage
- These connection types appear in the user interface when you click . However, these connection types are not supported.
- Cannot connect to a data source with a Generic JDBC connection
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Connecting to an unsupported data source by creating a Generic JDBC connection is not supported.
Virtualizing data
- Tables in a MongoDB data source might be missing when you virtualize
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When you create a connection to MongoDB, you only see tables that were created in the MongoDB data source before the connection was added.
For example, if you have 10 tables in your MongoDB data source when you create a connection, you see 10 tables when you start to virtualize the table. If a user adds new tables into the MongoDB data source after the connection is added and before you click Virtualize, Data Virtualization won't display the new tables under the Virtualize tab.
- Cannot assign a join view to a data request
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The data request workflow is not supported.
- Cannot create a virtualized table from files on remote data sources
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Creating virtualized tables from files such as CSV, TSV, and Excel files on remote data sources by using a remote connector is not supported. You can create a virtualized table from files in IBM Cloud Object Storage. For more information, see Creating a virtualized table from files in Cloud Object Storage in Data Virtualization.
Connections
- Accessing Data Virtualization using a URL displays an error
- Personal credentials are not supported in data source connections from Data Virtualization
- When you create connections from Data Virtualization to data sources, you can use shared credentials only. Personal credentials are not supported.
- Service level connections that are deleted must be manually removed from the Platform connections page
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If you add a service level data source connection on the Platform connections page. Later, if you click Remove to delete the service level connection, the connection remains on the Platform connections page. You must manually remove the connection from the Platform connections page to completely remove the data source connection.
page, that connection also appears on the - Service level connections must be updated from the same place that they were added
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If you add a service level data source connection on the Platform connections are not reflected in the service level connection.
page, you must update the connection from the same place. Any updates that are made to the connection on the - Query fails due to unexpectedly closed connection to data source
Users and groups
- When you add or edit a user in User management, the role might be not granted successfully because of a timeout
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When the user logs in to Data Virtualization, the user interface shows a message that indicates that the user is locked. For example, Your user ID "dv_ibmid_270000ead8" is locked. To unlock this account, click unlock or go to User management and click Unlock in the overflow menu. You cannot resolve this issue by unlocking the user in the user interface. A Data Virtualization Manager must grant the role to the user manually. For example, run the following command:
db2 grant role dv_admin to dv_ibmid_270000ead8