Different views

Question

hi experts,
we have 4 types of views.
1. database view
2.projection view
3.maintanance view
4.help view
i want to know the difference among them. can anyone plz help me to know abt individual view, and the difference among them. give me the data abt each view, n the difference among them.
thanks in advance for ur responce.

Answer 1

Different Types of Views
1. Database View
Creating a Database View Locate the document in its SAP Library structure
Procedure
1. Enter an explanatory short text in the field Short text.
You can for example find the view at a later time using this short text.
2. Define the tables to be included in the view in the Tables field of the Tables/Join conditions tab page.
Keep in mind that you can only include transparent tables in a database view.
3. Link the tables with
join conditions.
If there are suitable foreign keys between the tables, you should copy the join conditions from these foreign keys (see Structure link Foreign Key Relationships and Join Conditions).
Place the cursor on a table name and choose Relationships. All foreign keys to other tables defined for this table are displayed. Select the foreign keys and choose This graphic is explained in the accompanying textCopy. The join condition is now derived from the definitions in the foreign key.
If you only want to see the foreign key relationship existing between two tables, you must first select these two tables (click on the first column of the input area Tables) and then choose Relationships.
4. On the View fields tab page, select the fields that you want to copy to the view.
Choose Table fields. All the tables contained in the view are displayed in a dialog box. Select a table. All the fields contained in this table are displayed. You can copy fields by selecting them in the first column and choosing This graphic is explained in the accompanying textCopy.
You can also include an entire table in the view (see Includes in Database Views).
5. On the Selection conditions tab page, you can (optionally) formulate restrictions for the data records to be displayed with the view (see
Maintaining Selection Conditions for Views).
The selection conditions define the data records that can be selected with the view.
6. With Goto ® Technical settings, you can (optionally) maintain the technical settings of the database view.
You can define whether and how the database view should be buffered here. Proceed as for the technical settings of a table (see Structure link Maintaining Technical Settings). Note that only the settings for buffering can be maintained for database views.
7. On the Maintenance status tab page, select the
maintenance status of the database view.
If the view contains more than one table, the maintenance status read only cannot be altered.
8. Save your entries. You are asked to assign the view a development class.
You can change this development class later with Goto ® Object directory entry.
9. Choose This graphic is explained in the accompanying text.
Result
When a database view is activated, the corresponding view is also automatically created in the database if the base tables of the view were already created there.
At activation, a log is written; it can be displayed with Utilities ® Activation log. If errors or warnings occurring when the view was activated, they are displayed directly in the activation log.
If the base tables are not yet created in the database, this is recorded in the activation log. The view is nevertheless activated in the ABAP Dictionary. In this case you can create the relevant view on the database later with the database utility.
Other Options
Create documentation: You can create information about using the view with Goto
® Documentation. This documentation is also output for example when you print the view. Change data element of a view field: Select the Mod (Modify) column in the View fields tab page. The Data element field is now ready for input. You can enter a data element that refers to the same domain as the data element of the assigned table field here. Cancel the Mod flag if you want to use the data element of the assigned table field again.
Display view data: With Utilities
® Contents you can determine which data can be selected with the view. Display create statement: With Extras
® CREATE statement you can display how the view was created in the database. The statement that was executed when the version of the view currently being edited was created in the database is displayed. Check the definition of the view in the database: With Utilities
® Database object ® Check you can determine whether the definition of the view in the database is consistent with the active version of the view. With Utilities ® Database object ® Display you can display the definition of the view in the database. Check the runtime object of the view: With Utilities
® Runtime object ® Check you can determine whether the definition of the view in the ABAP Dictionary maintenance screen is identical to the specifications in the runtime object of the view. With Utilities ® Runtime object ® Display you can display the runtime object of the view.
2. Projection View
Creating Projection Views Locate the document in its SAP Library structure
Procedure
1. Enter an explanatory short text in the field Short text.
You can for example find the view at a later time using this short text.
2. Enter a table name in the field Base table.
A projection view always contains exactly one table.
3. Select the fields of the base table that you want to include in the view.
Choose Table fields. The fields of the table are now displayed in a dialog box. You can copy fields by selecting them in the first column and choosing This graphic is explained in the accompanying textCopy.
4. Save your entries.
You are asked to assign the view a development class. You can change this development class later with Goto ® Object directory entry.
5. Choose This graphic is explained in the accompanying text.
Result
The help view is activated. At activation, a log is written; it can be displayed with Utilities ® Activation log. If errors or warnings occurring when the view was activated, they are displayed directly in the activation log.
Other Options
Create documentation: You can create information about using the view with Goto
® Documentation. This documentation is output for example when you print the view. Change data element of a view field: Select column Mod (modification) for the particular view field. The Data element field is now ready for input. You can enter a data element that refers to the same domain as the data element of the assigned table field here. Cancel the Mod flag if you want to use the data element of the assigned table field again.
Change maintenance status: The
maintenance status determines how you can access the view data from ABAP programs (read only, read and change). Choose Extras ® Maintenance status. A dialog box appears in which you can select the maintenance status of the view. Check functions: With Utilities
® Runtime object ® Check you can determine whether the definition of the view in the ABAP Dictionary maintenance screen is identical to the specifications in the runtime object of the view. With Utilities ® Runtime object ® Display you can display the runtime object of the view.
3. Maintainence View
Maintenance View Locate the document in its SAP Library structure
Definition
Related data in several tables can be maintained together in a maintenance view.
Structure
A maintenance view has the samee key as its primary table. To ensure that the system can write the records inserted in a maintenance view correctly into the tables in the view, put all key fields of the primary table in a maintenance view.
Each entry in the primary table can have at most one dependent data record in the secondry table. The only exceptions are the text tables of tables in the view which have the additional key field Language. The system puts the logon language in the language field during the table maintenance. You cannot put the language field in the view explicitly.
You can maintain text table entries in other languages with the translation function in transaction SM30.
Caution
You must regenerate the maintenance dialog if you change the definition of a table/view with a generated maintenance dialog, e.g. add or remove fields, or change the maintenance attribute or a selection condition.
Maintenance Attributes
You can assign a maintenance attribute P to individual fields in the maintenance view definition in the Dictionary (SE11). It can be R (read only), H (hidden), or S (subset).
R (readonly)
A field flagged R is not ready for input by the user on the screen. When a new data record is created, it must be filled automatically in the background. To fill a field automatically in the background, create a routine for an event.
H (hidden)
A field flagged H is not displayed on the screen. This field must also be filled in the background by a routine at an event.
The system writes R and H fields to the database like all other fields when a new data record is saved.
S (subset)
A field flagged S restricts the work area.
The system only shows data records for which this subset field has the specified value. This restriction of the work area remains effective when you create new data records.
View Variant
You can define any number of view variants for an existing view. The view variants do not have their own generated maintenance dialogs, they use the base view. The view variants can differ from their base view by different selection conditions and a different field selection.
4. Help View
Creating Help Views Locate the document in its SAP Library structure
Procedure
1. Enter an explanatory short text in the field Short text.
You can for example find the view at a later time using this short text.
2. Enter the primary table of the view under Tables in the Tables/Join conditions tab page.
Only tables that are linked with the primary table (indirectly) with a foreign key can be included in the view.
3. Save your entries.
You are asked to assign the help view a development class. You can change this development class later with Extras ® Object directory entry.
4. If required, include more tables in the view. In a help view you can only include tables that are linked to one another with foreign keys.
Position the cursor on the primary table and choose Relationships. All existing foreign key relationships of the primary table are displayed. Select the foreign keys and choose This graphic is explained in the accompanying textCopy. The secondary table involved in such a foreign key is included in the view. The join conditions derived from the foreign keys (see Structure link Foreign Key Relationship and Join Condition) are displayed.
You can also include tables that are linked with a foreign key to one of the secondary tables already included. To do this, place the cursor on the secondary table and choose Relationships. Then proceed as described above.
For maintenance and help views, there are certain restrictions on the foreign keys with which the tables can be included in the view (see Restrictions for Maintenance and Help Views). The foreign keys violating these conditions are displayed at the end of the list under the header Relationships with unsuitable cardinality.
5. On the View fields tab page, select the fields that you want to copy to the view. The key fields of the primary table were automatically copied to the view as proposals.
Choose Table fields. All the tables contained in the view are listed in a dialog box. Select a table. The fields of the table are now displayed in a dialog box. Select the required fields in the first column and choose This graphic is explained in the accompanying textCopy.
6. On the Selection conditions tab page, you can (optionally) formulate restrictions for the data records to be displayed with the view (see
Maintaining Selection Conditions for Views).
The selection conditions define the data records that can be selected with the view.
7. Choose This graphic is explained in the accompanying text.
Result
The view is now activated. At activation, a log is written; it can be displayed with Utilities ® Activation log. If errors or warnings occurring when the view was activated, they are displayed directly in the activation log.
Other Options
Create documentation: You can create information about using the view with Goto
® Documentation. This documentation is output for example when you print the view. Change data element of a view field: Select column Mod (modification) for the view field. The Data element field is now ready for input. Enter the new data element there. You can enter a data element that refers to the same domain as the data element of the assigned table field here. Cancel the Mod flag if you want to use the data element of the assigned table field again.
Check functions: With Extras
® Runtime object ® Check you can determine whether the definition of the view in the ABAP Dictionary maintenance screen is identical to the definitions in the runtime object of the view. With Extras ® Runtime object ® Display you can display the runtime object of the view.
Regards,