3604894 - How to POST several OData V4 service entities at the same time

When attempting to POST more than one additional entity (for example, multiple items or related entities) to an existing Purchase Order, the request fails.
However, posting a single additional entity to the same Purchase Order works as expected.

SAP S/4HANA Cloud Public Edition

Use BATCH to combine several POST operations to achieve this goal.

For example, if you want to add two notes at the same time for a purchase order item, use a BATCH request to combine the two POST requests.

Request URI: /sap/opu/odata4/sap/api_purchaseorder_2/srvd_a2x/sap/purchaseorder/0001/$batch

Payload sample:( Consider 4500012345 number as an example )

--batch_boundary
OData-Version: 4.0
Content-Type: multipart/mixed; boundary=changeset_1
Content-Transfer-Encoding: binary

--changeset_1
Content-Type: application/http
Content-Transfer-Encoding: binary
Content-ID: 1

POST PurchaseOrderItem(PurchaseOrder='4500012345',PurchaseOrderItem='10')/_PurchaseOrderItemNote HTTP/1.1
OData-Version: 4.0
OData-MaxVersion: 4.0
Content-Type: application/json;odata.metadata=minimal

{"PurchaseOrder":"4500012345","PurchaseOrderItem":"00010","TextObjectType" : "F02","PlainLongText" : "Text from batch F02","Language" : "EN"}

--changeset_1
Content-Type: application/http
Content-Transfer-Encoding: binary
Content-ID: 2

POST PurchaseOrderItem(PurchaseOrder='4500012345',PurchaseOrderItem='10')/_PurchaseOrderItemNote HTTP/1.1
OData-Version: 4.0
OData-MaxVersion: 4.0
Content-Type: application/json;odata.metadata=minimal

{"PurchaseOrder":"4500012345","PurchaseOrderItem":"00010","TextObjectType" : "F05","PlainLongText" : "Text from batch F05","Language" : "EN"}

--changeset_1--

--batch_boundary--

api_purchaseorder_2, Post,  POST PurchaseOrderItem, Odata V4, API, Purchase order,S4_1c, S4_PC, S/4HANA Cloud,  , KBA , MM-PUR-PO-2CL , Purchase Orders (Public Cloud) , How To