C-create, R-read, U-update, D-delete OData Services Creation Using ABAP CDS Views
This article describes the fastest way of OData Services creation using ABAP Core Data Services. Details on @OData.publish annotation utilization, reference to Data Source CDS-Entity and import from DDIC Structure are given. Create, Update and Delete actions are shown on the custom transparent table data just to simplify the article and do not move focus from OData Service creation to business process requirements implementation.
“R” Type OData Service Creation. With using of @OData.publish annotation in ABAP CDS
Let us assume that we have any data table (probably in the custom namespace, just to simplify the demo case and get focused on OData service only, and not on SAP functional modules and class usage)
It is possible to create ABAP CDS view for it using SAP HANA Studio
During CDS activation OData service will be generated in the background
Service document looks like this:
“R” Type OData Service Creation. Using reference on ABAP CDS
Let us assume that we have any data table (probably in custom namespace, just to simplify demo case and get focused on OData service only, and not on SAP functional modules and class usage)
It is possible to create ABAP CDS view for it using SAP HANA Studio. Please consider that in this case there is no @OData annotation in use
During our next step we will Create Gateway Project via transaction code SEGW and refer it to the created in the previous step ABAP CDS
SAP will generate runtime objects based on reference to ABAP CDS
The service document looks like this:
“CRUD” Type OData Service Creation
Let us assume that we have any data table (probably in custom namespace, just to simplify the demo case and get focused on OData service only, and not on SAP functional modules and class usage)
It is possible to create ABAP CDS view for it using SAP HANA Studio (no @OData annotation is in use)
During our next step we will Create Gateway Project via transaction code SEGW and import DDIC Structure (use @AbapCatalog.sqlViewName value from ABAP CDS, please see the picture above)
If you are using complex CDS with associations (for Master-Details view, for example) you should additionally create Associations and Navigation Properties. This section will be added.
SAP will generate runtime objects
For “CRUD” type of OData Services we should set parameters of Entity Set and then implement each of them
Navigate to ABAP Workbench and redefine methods of *DPC_EXT class for CRUD operations
Here it is possible to point out SELECT statement directly to ABAP CDS for Get_EntitySet method
METHOD experimentset_get_entityset. SELECT * FROM zxeq1_lexprmnt01 INTO CORRESPONDING FIELDS OF TABLE @et_entityset ORDER BY PRIMARY KEY. ENDMETHOD.
If you set Searchable parameter of Entity Set then ABAP code implementation should look like the following
METHOD experimentset_get_entityset. DATA: lv_osql_where_clause TYPE string. "Prepare where clause lv_osql_where_clause = io_tech_request_context->get_osql_where_clause( ). "Select data SELECT * FROM zxeq1_lexprmnt01 INTO CORRESPONDING FIELDS OF TABLE @et_entityset WHERE (lv_osql_where_clause) ORDER BY PRIMARY KEY. ENDMETHOD.
If you additionally set Pageable parameter of Entity Set then ABAP code should look like the following
METHOD experimentset_get_entityset. DATA: lv_osql_where_clause TYPE string, lv_top TYPE i, lv_skip TYPE i, lv_max_index TYPE i. "Prepare top and skip lv_top = io_tech_request_context->get_top( ). lv_skip = io_tech_request_context->get_skip( ). IF lv_top IS NOT INITIAL. lv_max_index = lv_top + lv_skip. ENDIF. "Prepare where clause lv_osql_where_clause = io_tech_request_context->get_osql_where_clause( ). "Select data SELECT * FROM zxeq1_lexprmnt01 INTO CORRESPONDING FIELDS OF TABLE @et_entityset UP TO @lv_max_index ROWS WHERE (lv_osql_where_clause) ORDER BY PRIMARY KEY. "Process skip IF lv_skip IS NOT INITIAL. DELETE et_entityset TO lv_skip. ENDIF. "Process inline couter IF io_tech_request_context->has_inlinecount( ) = abap_true. SELECT COUNT(*) FROM zxeq1_lexprmnt01 WHERE (lv_osql_where_clause). es_response_context-inlinecount = sy-dbcnt. ELSE. CLEAR es_response_context-inlinecount. ENDIF. ENDMETHOD.
In Get_Entity method we should use ABAP CDS and other data type related objects and key field names
METHOD experimentset_get_entity. DATA: ls_data TYPE zcl_xeq1s_exprmnt01p_mpc=>ts_experiment. "Convert keys to data CALL METHOD io_tech_request_context->get_converted_keys IMPORTING es_key_values = ls_data. "Select data by keys SELECT SINGLE * INTO CORRESPONDING FIELDS OF @er_entity FROM zxeq1_lexprmnt01 WHERE uname = @ls_data-uname. ENDMETHOD.
If you set Creatable parameter of Entity Set then you should implement Create_Entity method and ABAP code could look like the following. In our current example we are using database table as target to INSERT data (in more complex and realistic business case SAP BAPI or functional modules or ABAP Classes should be used here to implement required business logic)
METHOD experimentset_create_entity. DATA: ls_data TYPE zxeq1_dexprmnt01. "Insert data in database MOVE-CORRESPONDING er_entity TO ls_data. INSERT zxeq1_dexprmnt01 FROM @ls_data. ENDMETHOD.
If you set Updatable parameter of Entity Set then you should implement Update_Entity method like the following sample. In our current example we are using database table as target to UPDATE data (in more complex and realistic business case SAP BAPI or functional modules or ABAP Classes should be used here to implement required business logic)
METHOD experimentset_update_entity. DATA: ls_data TYPE zxeq1_dexprmnt01. "Update data in database MOVE-CORRESPONDING er_entity TO ls_data. UPDATE zxeq1_dexprmnt01 FROM @ls_data. ENDMETHOD.
If you set Deletable parameter of Entity Set then you should implement Delete_Entity method like the following sample. In our current example we are using database table as target to DELETE data (in more complex and realistic business case SAP BAPI or functional modules or ABAP Classes should be used here to implement required business logic)
METHOD experimentset_delete_entity. DATA: ls_data TYPE zcl_xeq1s_exprmnt01p_mpc=>ts_experiment. "Convert keys to data CALL METHOD io_tech_request_context->get_converted_keys IMPORTING es_key_values = ls_data. "Delete data from database DELETE FROM zxeq1_dexprmnt01 WHERE uname = @ls_data-uname. ENDMETHOD.
As a result, there is the following OData Service Document created
This article shows a fast and simple way of OData Service creation with full CRUD functions support based on ABAP CDS technology. It is possible to see that wrapper for CRUD OData Service based on ABAP CDS could be created as fast as a few hours activity. What is needed is simply to add ABAP logic inside it that is mostly the same kind of activities we’ve done in ABAP development before web services usage. Additionally, OData Service created on ABAP CDS views is ready to be consumed by SAP HTML5 (UI5) Application and could either be deployed to your company local SAP Fiori Launchpad or to SAP Fiori Cloud Launchpad (Portal) from SAP Cloud Platform.
P.S. Please consider that in case of SAP Fiori Cloud Launchpad usage we have to wrap OData Service using SAP Cloud Platform OData Provisioning Service (that is covered in another article).
Nice Blog. There is one more way, where you can directly bind the CDS view to the entity. So we dont need to write the code to fetch the data. SADL layer will fetch the data for us with top, skip, filters.., applied automatically.
In the service implementation, right click on the entity and map to data source, here map the same to CDS view.
Thanks & Best Regards,
Hi Mahesh Palavalli,
Thank you for useful information!
Hello, Mahesh Palavalli,
Which is the other way we can directly bind CDS view to the entity?
Hi Mahesh Palavalli Is this BOPF ?
No, it is'nt.. it's just normal mapping of cds view to the entity set.. You can even map a database table or view..
Is there any way to pass on the CDS UI annotations automatically using this mapping editor method?
Hi Sarbjeet Singh
I don't think it is possible if we do like that. I've only observed the annotations flowing from the Odata service that is generated from the CDS view or via the referenced odata source.
Hi @Mahesh Kumar Palavalli
Is it possible to redefine methods for CDS, to apply addational data/logic not being covered by CDS?
I try to call method to include more data in entity while GET request is initiated for the entity.
Your help is much appreciated!
If the service is not generated from the CDS view then yes it is possible as you will be doing it via the reference odata source or entity set binding to individual cds view.
So in the dpc_ext class, redefine the required enitityset method and call the super class method again so that the SADL layer will take care of the actual read then after that manipulate the response.
is that what you are expecting?
Yes I do. You confirmed something I only could guess about. Thank you very much for your valuable response!
Is it possible to access data from a database table of another system in this method? What I need to achieve is to fetch data from another odata service and its entity.
I skipped data retrieval on the ABAP/backend side. My solution is to the stuff on frontend, accessing two different OData services.
Hi @Mahesh Palavalli,
Say the OData is generated via the reference odata source and the CDS contains aggregation annotation. If you manipulate the response in the dpc_ext class could it affect the guid generated for aggregation? or is the aggregation and guid generated after manipulating the response in the dpc_ext class?
I tested this and the aggregation has already been done by the time the data is available in the redefined get_entityset. So you cannot add or filter out rows of data as it will invalidate the totals. What you can do is calculate additional fields for display that will not affect the totals, e.g. fetch a text, etc. Because of pagination only a subset of data is available in the get_entityset, not all. This has the benefit that you can perform calculations on a subset of data which should be faster than the whole dataset.
Thanks for raising this topic .
I was under the impression that SADL technique can be used only for fetching data .Not for making any modification (Update , Delete ) .
Could you kindly share any article how to make modifications in a CDS view , using SADL .
The only two options I am aware of , for making modifications (Update , Delete ) are BOPF and the one mentioned by @Uladzimir .
I think those are the only ways with CDS views.
Thanks for the great document.
I tried to implement the above-explained method. will it only work for the custom dictionary object because in delete method you mentioned to delete it specifically?
I have a requirement to use standard I_MaterialStock view and it is required to remove or hide a field in Fiori query browser, can we achieve delete fields for standard views using the above method?
we have a requirement to hide/remove a certain field from standard view "C_MaterialStockActual". is there any other method to hide fields in a fiory application?
Uladzimir should have kept the 3 scenarios with unqiue names
experimentset_create_entity and experimentset_update_entity are both wrong
These result in NULL rows ie. spaces and zeroes; ABAP lingo initial
I could not get a good SAP Blog
But stepped out to https://www.zapyard.com/odata-and-sap-netweaver-gateway-part-v-crud-operations-in-odata-services/
Good vetted samples also in few other sites
CREATE_ENTITY shadowed on zapyard is a happy ending
UPDATE_ENTITY does the job but returns
~status_reason No Content
DELETE_ENTITY has the right code
Oversight in CREATE_ENTITY and UPDATE_ENTITY is probably author assuming that reader has the experience
I am new in the latest ABAP developments so was delayed!
Overall the blog was very useful to me
Mahesh Palavalli comment would be best explained with a concrete vetted example of "mapped datasource"
and CDS with BOPF for CUD
@OData.publish: true //To Make it BOPF Enabled
//This will Delegate the CRUD to Transactional CDS
//To define what all actions are enabled
createEnabled: true, deleteEnabled: true, updateEnabled: true }
As used by Amit Diwane in
Happy ending apart for UPDATE_ENTITY
By doubts how to avoid key update
how to update only the input content selected fields?
For perfect solution with optimistic locking (by Andre Fischer)
PDF by Andre Fischer on the many options https://assets.cdn.sap.com/sapcom/docs/2019/07/28ed1f77-587d-0010-87a3-c30de2ffd8ff.pdf
Could not find any reliable BOPF DRAFT based Fiori Odata example