Update table without GUI View or Fiori

UpdateTable

----------
Table 
----------
@EndUserText.label : 'Test'
@AbapCatalog.enhancementCategory : #NOT_EXTENSIBLE
@AbapCatalog.tableCategory : #TRANSPARENT
@AbapCatalog.deliveryClass : #A
@AbapCatalog.dataMaintenance : #LIMITED
define table ztest {
  key client : abap.clnt not null;
  key id     : abap.char(5) not null;
  string     : abap.string(0);
}

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CDS View:
-----------
@AbapCatalog.sqlViewName: 'ZIVTEST'
@AbapCatalog.compiler.compareFilter: true
@AbapCatalog.preserveKey: true
@AccessControl.authorizationCheck: #NOT_REQUIRED

@EndUserText.label: 'Test data maintenance'

@OData.publish: true

@ObjectModel: {
    createEnabled: true,
    draftEnabled: false,
    modelCategory: #BUSINESS_OBJECT,
    transactionalProcessingEnabled: true,
    updateEnabled: true,
    deleteEnabled: true,
    writeActivePersistence: 'ZTEST'
}

define view zI_Test
  as select from ztest
{
  key id     as Id,
      string as String
}

-----------
Use Postman to POST:
-----------
{
  "d" : {
        "Id" : "1",
        "String" : "Foo"
    } 
}