10 Migrating an Object Type to a Different Object Type
10.1 Convert Attribute Views and Analytic Views to Graphical Calculation Views
In the future, as graphical calculation views becomes the standard for creating information views, SAP recommends that you create graphical calculation views for all analytical use cases and also convert existing analytic views or attribute views to graphical calculation views.
Prerequisites
You have the permissions to perform the modeling activities such as, create, activate, and data preview information views and analytic privileges.
Before you perform the migration activity, you have read the section, Best Practice: Migrating an Object Type to a Different Object Type [page 202].
Context
SAP HANA modeler (SPS 11 version onwards) allows you to perform a migration activity within the SAP HANA modeler tool to convert analytic views or attribute views to graphical calculation views. The migration activity converts and replaces the target attribute views or analytic views with new graphical calculation views having the same name.
Procedure
1. Launch SAP HANA studio.
2. In the Quick View pane, choose Migrate.
3. Select a system where you want to perform the migration activity.
4. Choose Next.
5. Select Attribute views and analytic views to calculation Views.
6. Create a migration log.
Migration log records changes that modeler performs during this migration activity and provides information on the status of each migrated content.
a. Select Create Migration Log.
b. Browse to the folder location where you want to save the migration log.
7. Choose Next.
8. Select an object or a package that contains the objects that you want to convert to graphical calculation views.
9. Choose Add.
10. If you want to use the hidden columns of analytic views or attribute views and if you want to perform any operations using these columns in the new graphical calculation views, select Unhide Hidden Columns.
Note
The behaviors of hidden columns are different for graphical calculation views. If you convert the views without selecting the checkbox, then the hidden columns appear as proxies in the new graphical calculation views. If you want to use these hidden columns in the graphical calculation views and also to avoid activation errors due to missing columns, it is necessary to unhide the hidden columns.
11. Choose Next.
Note
Simulate the migration activity. If you want to perform a migration activity without impacting any of the exiting objects, for example, to preview the impact of the migration activity, then you can simulate using the Copy and migrate feature. Simulating a migration activity does not adjust reference of impacted objects. For more information, see Simulate a Migration Activity [page 198].
12. Confirm changes
In the Impacted Objects dialog, modeler displays the list of objects that you have selected for the migration activity, the impacted objects and the references of impacted objects that modeler can automatically adjust.
a. After verifying the changes, choose Finish to proceed and complete the migration activity.
Note
If the impacted objects are in different package and not in the package that you have selected for migration, then modeler cannot automatically adjust the references of those impacted objects. In such cases, it is recommended that you group all impacted objects in a single package and select this package in a new migration activity. You can refer to the migration log to identify those impacted objects for which modeler could not automatically adjust the references.
Related Information
Migration Impact [page 193]
Simulate a Migration Activity [page 198]
Undo Migration Changes [page 199]
Activate Migrated Objects [page 200]
Migration Log [page 201]
10.1.1 Migration Impact
An analytic view or attribute view comprises of entities such as the joins, columns, analytic privileges, view properties and so on. The behavior of some of these entities change after you convert the analytic view or attribute view to graphical calculation view.
For converting an attribute view or analytic view to graphical calculation view, it is necessary to modify the behavior of some of its entities. The following table provides information on the entities and the impact of migration on the behaviors of such entities.
Table 69:
Entity Impact on Behavior
row.counter Analytic views contain a row.count column that modeler uses internally to calculate the result of select count(*) queries. You can also use row.count in SQL statements, SQL script and calculation views built on top of such analytic views.
The migration activity to convert the analytic view to graphical calculation views, updates the calcula
tion view property, Row Counter with value of row.count. This is to ensure that modeler generates the column into the catalog calculation view with same semantics as that of the analytic view. If you do not want to use this column in SQL or upper views, remove it by setting the view property Row Counter to
<BLANK>. If the property is set to <BLANK>, the column is no longer visible in the calculation view, but is used internally only to calculate the result of select count(*) queries.
Referential Joins All referential joins in the analytic views and attribute views are preserved after converting these views to new graphical calculation views. However, if a filter is applied on any of the tables in the join, then all referential joins, which exists in the join path of this table and the fact table, are converted to inner joins in the new graphical calculation views.
Filters All column filters in the attribute views and analytic views are converted to an equivalent filter expres
sions in the new graphical calculation views.
Input Parameters If you have created any input parameters in the analytic views or attribute views, then the input param
eter definitions are preserved in the new graphical calculation views.
.description col
umns
If you are using .description columns in analytic views or attribute views to store attribute descrit
pions, then these columns are converted to Label Columns in the new graphical calculation views after migration.
Translation Texts All translation texts available in the attribute views and analytic views are preserved in the new graphi
cal calculation views.
Derived Attribute Views
Consider you are converting a derived attribute view, V_DERIVED_ATTRIBUTE, which is derived from the base attribute view, V_BASE_ATTRIBUTE. Modeler converts these views to graphical calculation views by creating two identical calculation views, V_DERIVED_ATTRIBUTE and V_BASE_ATTRIBUTE.
These views are independent of each other. Any change to V_BASE_ATTRIBUTE does not impact V_DERIVED_ATTRIBUTE.
Entity Impact on Behavior Client Dependent
Views
In analytic views or attribute views, if the session client for a user is set to NULL, the system does not filter the data and displays data of all clients. But, after converting such analytic views or attribute views to graphical calcualtion views, the session client value is preserved, but the system does not re
turn or display any data.
Hidden Columns If you are converting analytic views or attribute views that have hidden columns, then these columns are not visible and are available only as proxies in the new graphical calculation views. The migration tool allows you to unhide the hidden columns before converting them to new graphical calculation views. This helps avoid activation errors due to missing columns and also to use the hidden columns in the graphical calculation views.
Relational Optimi
zation
Relational optimization is not supported in graphical calculation views.
Generate Concat Attribute Prop
erty
Generate concat attribute property is not supported in graphical calculation views.
Temporal Joins Temporal Joins are not supported in graphical calculation views.
Search Attributes Search attributes are not supported in graphical calculation views.
Analytic Privi
leges
The value of the view property, Apply Privileges of analytic views or attribute views are preserved in the new graphical calculation views. For example, if you are converting an analytic view with the property Apply Privileges set as Classical Analytic Privileges, then the new graphical calculation view also con
tains the same value for its Apply Privileges. property.