Update Physical Data Service Metadata
This page last changed on Mar 28, 2008.
Oracle Data Service Integrator Documentation > Data Services Developer's Guide How To Update Physical Data Service MetadataWhen you first create a physical data service its underlying metadata is, by definition, consistent with its data source. Over time, however, your metadata may become "out of sync" for several reasons:
In some cases relationships between data services will be preserved during metadata update. See Using the Update Source Metadata Wizard, for details. TopicsIn Project Explorer you can use the right-click menu option Update metadata to see if there are any differences between your source metadata files and the underlying source. Update Metadata Option in Project ExplorerThe Update metadata option can be used with:
Metadata update cannot be applied to data services based on:
Scope of Metadata UpdateWhen you run the Metadata update option, differences between your physical data service and the underlying data source are categorized according to the following scheme:
If there are no differences between your metadata and the underlying source, the Update metadata wizard will report up-to-date for each data service being verified. In the case of an unavailable data source, the issue likely relates to connectivity or permissions. In the case of the other types of discrepancies, you need to determine when and if to update data source metadata to conform with the underlying data sources. Important Considerations When Updating Source MetadataThe update metadata operation can have both direct and indirect consequences. Source metadata should be updated with care by someone who is quite familiar with the underlying data source. For example, if you have added a relationship between two physical data services, updating your source metadata may remove the relationship from both data services. If the relationship appears in a model diagram, the relationship line will appear in red, indicating that the relationship is no longer described by the respective data services. Direct and Indirect EffectsDirect effects apply to physical data services. Indirect effects occur to logical data services, since such services are themselves based — at least indirectly — on physical data services. For example, if you have created a new relationship between a physical and a logical data service (not a recommended practice), updating the physical data service can invalidate the relationship. In the case of the physical data service, there will be no relationship reference. The logical data service will retain the code describing the relationship but it will be invalid if the opposite relationship notations is no longer be present. Using the Update Source Metadata WizardThe Update metadata wizard allows you to update your source metadata.
You can perform a metadata update on your entire dataspace project, folders from the project, or any qualified data service. Generally speaking, metadata updates should be performed as specifically as possible.
After you select your target(s), the wizard identifies the metadata that will be verified and any differences between your metadata and the underlying source. You can select/deselect any data service listed in the dialog using the checkbox to the left of the name. You can also choose to select/deselect specific changes for the data service using the checkbox to the left of the change description. The following screen capture is from a Update Metadata command for the ElectronicsWS project in the sample application. Details related to the changes that will be made when the metadata is updated appear in the lower panel of the window. Original Source and Refactored Source DetailsThe upper portion of the Update metadata plan shows the changes to be performed. In some cases items are presented and selected (checked). In other cases items are presented but unchecked. In the details view, the left-hand side shows the current source (called Original Source). The right-hand side shows what the result will be after metadata update (called Refactored Source). Your only options in the dialog are to select or deselect specific changes using the adjacent checkboxes. Up/down arrows are available on the Update Metadata titlebar to move through the possible changes. (The Filter Changes option icon next to the arrows is not applicable to metadata update and is not active. Update Metadata Wizard Navigation ArrowsInspecting and Reverting Changes Using Local HistoryYou can use the Local History option provided with Eclipse to review changes that have been made through the Metadata Update Wizard. Here are the steps involved:
It is also often possible to revert a metadata update using a similar mechanism:
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