View Creation

8/6/2019 View Creation

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View creation

Views

General Concept:

In the language of relational databases, a view is a virtual table, thatis, a table that is not actually physically stored, instead being derived

from one or more other tables.

In the simplest case, this derivation process can involve simplysuppressing the display of one or more fields from a base table

(Projection) or transferring only certain records from a base table tothe view (Selection). More complicated views can be assembled from

several base tables, with individual tables being linked using the

relational Join operation.

The way views are defined in relational database systems, it is possible

to use any desired combination of the three fundamental operations -projection, selection, and join - with the single constraint being that

only views derived from a single base table, i.e. without applying the

join operation, may be relationally operated on in turn.

SAP view concept:

The SAP view concept is based on the fundamental relational

operations, which are projection, selection, and join.

However, whereas in strictly relational systems links between differenttables must be dynamically forged using join operations, the SAP data

model with its foreign key concept offers the possibility of staticallydefining semantic foreign keys between tables in the ABAP

Dictionary.

In order to ensure that only semantically meaningful views will begenerated, the view definition used only permits tables to be joined

that are already linked by appropriate foreign keys in the ABAPDictionary.

This definition of views allows logical cross-sections of data to be

generated in response to the needs of specific applications, so that therequired data can be directly and efficiently accessed.

The following view types are supported:



• Database views

• Projection views

• Help views

• Maintenance views

Database views

The view defined in the ABAP Dictionary is reproduced in the

underlying database. You can use both ABAP Open SQL and ABAP

Native SQL to access such views from ABAP programs, but you canonly define them using transparent tables. If you define a database

view using only one table, you can make changes to the view. Fordatabase views containing several tables, however, only read accesses

are allowed

Projection views (table projection only)

Projection views are used to suppress certain fields from a table in theinterests of minimizing interfaces. A projection view can only refer to

one table and, in contrast to database views; you cannot specify anyrestrictions with regard to table type. This view type also permits both

read and writes accesses with ABAP Open SQL.

Help views

Help views are used as the selection method of elementary search

helps if the selection is too complex to be defined with a single

database table. In contrast to database views, help views implementan outer join. For this reason they are suitable for linking

supplementary information such as explanatory text from secondarytables. If the supplementary information were missing in an inner join,

the entire dataset would not be selected.

If the selection is only to use a table and its text table , it is sufficient

to specify the table directly as selection method of the search helpsince the fields of the text table can also be used as parameters in thesearch help in this case.

You should not use a help view if you expect the selection to be

restricted frequently with fields of the secondary tables. In this case



you should create a database view instead. You might also have tocreate suitable indexes for the base tables.

You can only speed up selection with help views if you restrict the

primary table. When accessing help views with the help processor,

special selection routines are generated. These routines always firstmake the selection using the primary table and then use the recordsfound as a key for selecting the supplementary information.

Notes

1. Direct access to help views is not possible.2. Prior to Release 4.0 help views were automatically used to

define the check table help for the primary table of the help

view. This is no longer valid as of Release 4.0.You can get the same effect by creating a suitable search help

and attaching it to the check table

Maintenance views

Maintenance views provide you with a business view of the data. You

can change it either with the table maintenance transaction SM30,

which allows you to maintain data from the base tables in a view atthe same time, or with the customizing transaction. The mechanisms

for data maintenance such as screens and processing programs can becreated with a special transaction (SE54).

1) In order to create a VIEW go to the T-Code SE11. Creation of

view is only possible if there is a foreign key relationship

between the two or more tables. Creation of view is also startedwith either Y or Z.



Give view name and click on create.

Give Short description then give two or more tables, which are having

foreign key relationships and then click on relationships



Select the check box and then click on copy. It gives the tablesnames along with the filed, which is common in the tables.



Then click on view fields tab and click on tables’ fields.

Select one table and click on Choose, then select what ever fields wewant from that table and click on copy.



Do same process for the 2nd table also.

Click on save, check and Activate. And then click on contents tab.



Click on execute.

This is the creation of VIEW

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View Creation