Verify the model in your existing environment 
.
Open and upgrade the model .
Verify and repair the model .
Upgrading a model prepares the model to take advantage of the new features in Cognos 8.
To upgrade your model, follow these steps:
Verify the model in your existing environment .
Open and upgrade the model .
Verify and repair the model .
The upgrade process does not resolve any problems that existed in your model prior to upgrading. Before upgrading the model, we recommend that you verify your model and fix any reported problems in your existing environment.
When upgrading from Cognos ReportNet to Cognos 8.3,
you must ensure that dimension information is set correctly in the
Cognos ReportNet model and then verify the model and fix errors.
In Cognos ReportNet, dimension information combined the concept
of uniqueness with the concept of dimensional hierarchies. In Cognos 8,
the concept of dimension information is divided between determinants
and hierarchies for regular dimensions. Determinants control uniqueness
and granularity. This control is required for relationally-based
query subjects, particularly multiple-fact, multiple-grain queries .
Hierarchies for regular dimensions address dimensional concepts
of hierarchies, levels, keys, and attributes for all data sources.
When you upgrade the model, you can use the dimension information to create query subjects with determinants or regular dimensions. Thus you must ensure that dimension information was specified correctly in your ReportNet model. When reviewing dimension information, you must understand how the dimension information is applied to the query subject and how you will use the query subject in the Cognos 8 model.
Before upgrading the model to Cognos 8, we recommend that you review your ReportNet model using the Modeling in Framework Manager for Predictable Queries and Results paper, which is available from the Cognos support Web site (http://support.cognos.com).
When you open an older model in Framework Manager, you are notified that the model must be updated.
When upgrading from Cognos ReportNet to Cognos 8.3, you should
understand the impact of governors that
are set during upgrade
review the data types that have changed
understand the impact on query subjects based on SAP BW metadata
If you are upgrading a model that is segmented or linked, see Upgrading Segmented and Linked Projects.
Several governors are set automatically during the upgrade process:
The Allow enhanced portability at run time governor is selected.
This governor is used when upgrading a Cognos ReportNet 1.x model. It prevents rigid enforcement of data types so that a Cognos 8 model can function as a ReportNet 1.x model until you update the data types in the metadata. After you have verified that the model has been upgraded successfully, clear this governor.
The status property of all data source query subjects is set to Needs Re-evaluation. The query engine ignores the data types in the model that are flagged as Needs Re-evaluation and retrieves the data type information from the data source. This may have a slightly negative impact on performance when running reports.
The Allow dynamic generation of dimension information governor is selected.
This governor ensures consistent behavior with Cognos ReportNet by deriving a form of dimension information from the relationships, key information, and index information in the data source.
When this governor is selected and a model contains query subjects but no dimensions, Cognos 8 generates queries that avoid double-counting. This also provides backward compatibility with ReportNet. When you verify the model, you see a warning when this governor is selected.
The Shortcut Processing governor is set to Automatic.
This governor controls how shortcuts are processed by Cognos 8. When the governor is set to Automatic, the model works the same as in ReportNet, that is, a shortcut that exists in the same folder as its target behaves as an alias, or independent instance. However, a shortcut existing elsewhere in the model behaves as a reference to the original. When you create a new model, the Shortcut Processing governor is always set to Explicit.
The Suppress Null values for SAP BW data sources governor is selected for SAP BW metadata only.
This controls the creation of outer joins in models based on SAP BW metadata.
Some queries can be very large because null values are not filtered out. Null suppression removes a row or column for which all of the values in the row or column are null (empty). Null suppression is performed by SAP BW. This reduces the amount of data transferred to the Cognos 8 studios and improves performance.
Cognos 8 added support for additional data types. This may change how data types are mapped between Cognos and the source data on metadata import.
Mapping of these data types varies by data source vendor.
The primary areas of change are as follows:
| Data Type in Cognos ReportNet | Data Type in Cognos 8 |
| char | nChar |
| decimal | numeric |
| varChar | nVarChar |
| varChar | timestampTZ |
| varChar | IntervalTZ |
Data types are stored in the model so that Cognos 8 can avoid going to the data source to determine the data types for query items, resulting in improved performance.
Some query items may appear broken after the upgrade, particularly calculations. For example, the data type of the underlying items for a calculation changed so it is not possible to automatically assign a data type to the calculation. Another example is you saved a calculation that uses a prompt without testing it. For these cases, test the calculation or query item that is affected to correct the data type.
A query subject that is based on SAP BW metadata is not converted to a dimension. Instead, the upgrade process creates a hidden dimension and a new model query subject that have the same name and query items as the original query subject. The model query subject points to the newly created hidden dimension, which is used to maintain compatibility with existing reports.
Prior to upgrading, conformed dimensions are represented by query subject shortcuts. During upgrade, the conformed dimensions are not altered. The query subject shortcuts are left intact, but the targeted SAP BW query subjects are replaced by model query subjects corresponding to the hidden dimension.
Model query subjects that do not contain levels and hierarchies are converted to measure dimensions.
After upgrading, review the model to ensure that the newly created regular and measure dimensions meet your analysis and reporting requirements. You should only conform dimensions as required to fulfill your reporting and analysis needs.
If you are developing a new application based on an existing model and you are not required to support existing content, you can delete conformed dimensions and re-import the objects from your SAP BW data source. This creates regular dimensions without the underlying query subjects.
After updating the metadata, Framework Manager prompts
you to verify the model. You will see at least one warning for each
object that contains dimension information or one of the data types
listed previously . We recommend that you check one namespace
at a time in large models. You can also check an individual object.
Verifying the model separately from the upgrade process offers a number of advantages. You can open an existing model and upgrade and publish without any changes in query functionality. You can take the time to reassess model requirements. You can continue to design the production model and publish it without dimensional information. For models created with Cognos ReportNet, you can move to dimensions and determinants gradually.
When upgrading from Cognos ReportNet to Cognos 8.3, you need
to convert query subjects with dimension
information to query subjects with determinants or to dimensions
to select and repair objects
If you make changes to the model before verifying it, you should not change the determinants. Doing so may result in losing the dimension information, which will prevent a successful model verification later.
In Cognos ReportNet, dimension information combined the concept of uniqueness with the concept of dimensional hierarchies. In Cognos 8, the concept of dimension information is divided between determinants and hierarchies for regular dimensions. Determinants control uniqueness and granularity. This control is required for relationally-based query subjects, particularly multiple-fact, multiple-grain queries. Hierarchies for regular dimensions address dimensional concepts of hierarchies, levels, keys, and attributes for all data sources.
Query subjects with dimension information are not converted to determinants or dimensions during the upgrade. The metadata previously specified by dimension information is preserved in the model and continues to exist for query subjects until those query subjects are repaired. You cannot change this dimension information in Cognos 8. You can upgrade the dimension information to determinants or dimensions. Until you upgrade the query subject, Cognos 8 uses the dimension information previously specified in Cognos ReportNet.
If you decide to make changes to the model without verifying it after the upgrade, do not make changes to the determinants because you may lose the dimensional information.
Use determinants if you want to preserve existing reports while extending your application.
Determinants reflect granularity by representing subsets or groups of data in a query subject and are used to ensure correct aggregation of this repeated data. Determinants are most closely related to the concept of keys and indexes in the data source and are imported based on unique key and index information in the data source.
Unlike dimension information, model query subjects inherit determinants that are specified for the underlying query subjects. We recommend that determinants be specified as early as possible in the model, typically on the data source query subject. In cases where different determinants are specified for different granularity control, you should either create multiple instances of the data source query subject or remove determinants from the data source query subject and create new determinants on each model query subject requiring different granularity control.
Use dimensions if you want to use your model in Analysis Studio, enable drilling up and down in reports, or access member functions in the studios. Only regular dimensions are created. During upgrade, sufficient metadata does not exist to create measure dimensions so you must create them manually. You can then relate the dimensions to the measures by setting scope in the model.
It is important to understand that if you upgrade query subjects to dimensions, the names of the query items in your model are changed. For example, a query item previously qualified as namespace.query subject.query item now has the name namespace.dimension.hierarchy.level.query item.
Because this name change is likely to invalidate existing reports, we recommend upgrading query subjects to dimensions only when you want to leverage an existing model to build a new application that requires dimensional capability.
Dimension information is mapped to determinants and dimensions as follows.
Dimension information | Determinants | Dimensions |
Hierarchies | For relational data sources, the first hierarchy is used to create the determinant. | Hierarchies For SAP BW data sources, alternate hierarchies are upgraded to alternate hierarchies of a dimension. |
Levels | Determinants, either uniquely identified or group by | Levels The first level of the hierarchy is automatically defined as the All level. It contains a single root member, which represents the top level of the hierarchy. You cannot delete or move the All level. You can change its name, description, and screen tip. |
Keys | If Unique Key is not selected, key segments from higher levels are included in the key. | _businessKey role |
If Unique Key is selected, only the key segment, or segments, for the level are included in the key. | Unique Level | |
Alphabetically first text attribute | _memberCaption role | |
Attributes | Attributes Unassociated attributes are assigned to the last determinant, which generally corresponds to the lowest level. | Can be manually assigned to be _memberDescription role, custom role, or no role |
After converting query subjects with dimension information to query subjects with determinants, you must review the following:
Uniquely Identified
When you define a unique determinant, you are indicating that the key contains enough information to identify a group within the data.
Group By
When you define a non-unique determinant, you should specify group by. This indicates to Cognos 8 that, when the keys or attributes associated with that determinant are repeated in the data, it should apply aggregate functions and grouping to avoid double-counting.
Multiple, or alternate, hierarchies that existed in Cognos ReportNet
If two hierarchies existed on a query subject in Cognos ReportNet, only the first hierarchy is upgraded to a determinant for relational data sources. You must create a second query subject and manually specify the determinants for the other hierarchy.
For SAP BW data sources, alternate hierarchies are upgraded to determinants.
After converting query subjects with dimension information to dimensions, you must review the following:
_businessKey role
This role represents the key for the level and can be assigned to only one attribute in a level.
Unique Level
A unique level indicates that the keys of the levels above are not necessary to identify the members in this level.
_memberCaption role
To leverage member functions in the Cognos 8 studios, you must assign a _memberCaption role to each level in a dimension. If there are no attributes for the level, the absence of a caption is highlighted when you verify the model.
All captions must have the string data type. If there is no attribute of this type available, create a calculation that is a string data type and assign the _memberCaption role to the new item. This is primarily an issue for Analysis Studio.
Attributes
In general, all other attributes should be included in the dimension and associated to the correct level. By default, they are included with no role. You have the option to create custom roles or assign attributes to existing roles.
Multiple Hierarchies
A regular dimension may have multiple hierarchies; however, you can use only one hierarchy at a time in a query. For example, you cannot use one hierarchy in the rows of a crosstab report and another hierarchy from the same dimension in the columns. If you need both hierarchies in the same report, you must create two dimensions, one for each hierarchy.
The repair process first evaluates all selected items. This evaluation automatically resolves issues with new data types and prompts you to repair dimension information in the model.
You can select one or more check boxes of items and repair them.
The following warnings may appear when you verify and repair an upgraded model:
| Warning | Description |
| Needs reevaluation | This message is most often related to data type changes. The majority of items with this warning can be selected for repair. The repair option provides options for evaluating and upgrading specific elements of metadata. |
| Join expression conflicts with the determinant information defined in the query subject | Sometimes the index and key information specified for a query subject implies a level of granularity that does not match the relationships specified on a query subject. |
| None of the query items in this level have a caption role specified | When defining levels, you must ensure that a business key and caption roles are specified. These roles are needed for member functions in the Cognos 8 studios and to assist in the member-oriented tree in Analysis Studio. All captions must have the string data type. If there is no attribute of this type available, create a calculation that is a string data type and assign the member caption role to the new item. This is primarily an issue for Analysis Studio. |
| One or more determinants that describe the keys and attributes of the query subject should be specified | Determinants are based on key information in the data source. It is possible that no determinants exist for a query subject upgraded from Cognos ReportNet, especially for a model query subject. We recommend that you use determinants to specify the granularity of the data in the query subject and the functional dependencies between query items. However, it is not mandatory to specify determinants for query subjects that represent a single level or fact data. |
