SAP CDS view自学教程之二：当SAP CDS view被激活时，背后发生了什么

You paste the following source code for a simple CDS view into ABAP development studio and activate it:

@AbapCatalog.sqlViewName: 'zjerrySQL0208'
@AbapCatalog.compiler.compareFilter: true
@AccessControl.authorizationCheck: #CHECK
@EndUserText.label: 'test 233'
@ObjectModel: {
   createEnabled,
   deleteEnabled,
   updateEnabled
}
define view Zjerrytest20160208
as select from spfli association [0..1] to scarr as _scarr
on _scarr.carrid = spfli.carrid {
       key spfli.carrid,
       key _scarr.carrname,
       key spfli.connid,
       spfli.cityfrom,
       spfli.cityto
}

And you would like to know what objects are automatically generated during CDS view activation.

Automatically generated ABAP objects during CDS view activation
You could query table TADIR with following parameters:

And get answer:
DDLS: Data Definition Language SourceSTOB: Structured Object

The relationship among these objects is listed below:

And if you use the same approach described in tutorial part1, you can realize that lots of database tables “DD*” are involved during CDS view activation, for exampleDDLDEPENDENCY. A small tip here is, if you click “Display Object List” button, you will navigate to the package where other related ABAP artifacts within the same package are displayed as well.

Now we can go through each database table one by one.

Automatically inserted table entries during CDS view activation

Several table entries are inserted to the database tables in package SDDL during view activation.

DDDDLSRC

Query this table by specifying DDLNAME as CDS view name we specified in ABAP development studio, the name after keyword “define view” : Zjerrytest20160208, and we can find view source code stored in field SOURCE.

DDDDLSRC02BT
Text table which stores the view description specified via [e-mail].

DDHEADANNO

It stores all header annotation specified in CDS view source code with corresponding value.

DDLDEPENDENCY

It maintains relationship between the CDS core entity and automatically generated database view.

要获取更多Jerry的原创文章，请关注公众号"汪子熙":