Call of Segments in a Logical View

In the Logical View editor, you can call Segments and Logical Views from the -CE Lines tab. In this context, a Segment that is called in a Logical View is considered as an elementary Data Element. When you enter or select a Segment call line in the -CE Lines, a definition section for this call line opens. You must indicate some information such as the Logical View attributes directly in the call definition section. Other information such as the data transfer or the subschemas are to be specified in a wizard that you open from this section.

Occurs
In this field, you enter the number of occurrences on 3 numeric characters. It corresponds to the OCCURS clause. It is not possible to create a repeated group area apart from the repeated structure (see the Data Type field). Repeated Data Elements are not authorized in graphic applications.

Logical View attributes

Data type
When a client calls a selection service, this service can implement an extraction method and its parameters by value. The Business Component that answers the call must recognize the extraction method and its parameters to correctly complete the service. The only way to send this information is through the message that is sent by the client.

The extraction method is sent to the Business Component through the technical part of the message. Parameters must be described in the application part of the message, that is in the Logical View.

In the Data type field, you specify the parameters by value for all the extraction methods that can be used by the Logical View. To do so, you call defined Data Elements. For each parameter, you enter the E type, which indicates that it is a parameter. Each identifier Data Element (U type) is an implicit parameter. The other Data Elements that describe the contents of the Logical View cannot be used as parameters. The E-type Data Element does not belong to the description of a Logical View. If necessary, you can define and call a child Data Element.
Table 1. Specification of the data type
Options Description
None Data Element that is not used as a parameter. For the Data Elements that describe the Logical View.
U: identifier for paging Data Elements that are to be used as selection criteria or start key for the reading of data occurrences in the database. Identifier for the paging of a list for the client. As output from the server, it contains the selection criteria values of the next page.
R: repeated structure There is only one repeated structure for a Logical View. A repeated structure is specified in the group Data Elements. This Data Element indicates the beginning of the repeated Data Elements. The end of the repeated Data Elements is deduced from the number of Data Elements in a group. The number of occurrences must be indicated in the Number of occurrences field in the Logical View definition.
E: extraction parameter The Data Element is used as a parameter for an extraction method. The E type Data Elements must be entered in the -CE lines before the Data Elements that describe the Logical View contents. Each identifier Data Element (U type) is an implicit extraction parameter. The other Data Elements that describe the Logical View cannot be used as parameters. If necessary, you can define and call a child Data Element.
Data Element presence
For each called Data Element, select one of the following check options in the list:
Table 2. Specification of the Data Element presence
Options Description
O: required Required Data Element. The check for its presence is generated in the client, and in the Business Component if CHECKSER=YES.
Note: It includes checks in relation to the Data Element description.
P: required Required Data Element. The check for its presence is generated only in the Business Component, if CHECKSER=YES.
Note: It includes checks in relation to the Data Element description.
Blank The checks that are specified in the Data Element description are generated in the client, and in the Business Component, if CHECKSER=YES.
F: optional The checks that are specified in the Data Element description are only generated in the Business Components if CHECKSER=YES.
Redefines
Redefinition is possible within a Segment or Logical View. It generates the COBOL REDEFINES clause. The Data Element that contains this option redefines the Data Element of the same COBOL level that precedes it in the -CE lines. If a Data Element that redefines another Data Element is contained in a group, it is considered to be an elementary Data Element. It must be taken into account in the calculation of the number of Data Elements that are contained in a group (except for DL/1 database Segments).
Note: When Data Elements are redefined, their respective lengths are not taken into account. It is your responsibility. The redefined Data Element length is used for the address calculation. Redefined Data Elements are ignored when generating for the Database Description function. If the Redefines box is checked, no initial value can be entered.
To redefine a Data Element, select the Redefines option. A Set of Redefines line is created in the -CE lines. It contains the redefined Data Element and the preceding Data Element of the same level in the tree structure. You must then define the Occurs option in the Set of Redefines section.

More

Click More to open a wizard where you indicate transfer options or specify subschemas.
Note: To open this wizard, you can also click the button that appears when you click the columns Subschemas, Transfer direction, Transfer operator, and Transfer area directly in the table of the tab.

-G Lines

Click -G Lines to define -GC lines (comments), -GE lines (error messages), and -GG lines (generation elements) for each Segment that is called in the Logical View.


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