Parameters in Views

Use as expressions, for example in:

• Operator expressions, e.g. calculations
• Arguments of SQL functions
• WHERE and ON conditions

Access to a parameter is done using
$parameters.<parameter>

Definition follows this pattern:

define view entity ZI_User
  with parameters
    p_user : xubname
  as select from ZBC_USERS
{
  ...
}

Exercise – CDS Parameters

Extend the previous exercise with expressions in the field list:

• The width of the column SummaryShort should be controlled by a parameter pSummaryShortLength.
• For the threshold values between PrioCat A, B, and C, introduce two parameters pLevelA and pLevelB.

Define the required parameters and adjust the expressions in the view entity accordingly.

Client Handling – Example

@AbapCatalog: { sqlViewName: 'ZJB_DEMO',
                compiler.compareFilter: true,
                preserveKey: true }

@AccessControl.authorizationCheck: #NOT_REQUIRED
@EndUserText.label: 'My First CDS View'
define view zjb_cds_demo
  as select from zbc_tasks as t

    left outer join zbc_users as u on t.assignee = u.user_id
{
      // Block mode: Alt + Shift + A
      // Pretty Printer: Shift + F1
  key t.task_key    as TaskKey,
      t.summary     as Summary,
      t.status      as Status,
      t.project     as Project,
      t.description as Description,
      t.assignee    as Assignee,
      u.firstname   as Firstname,
      u.lastname    as Lastname,
      t.type        as Type      
}

CREATE OR REPLACE VIEW "ZJB_DEMO" AS SELECT 
  "T"."CLIENT" AS "MANDT", 
  "T"."TASK_KEY" AS "TASKKEY", 
  "T"."SUMMARY" AS "SUMMARY", 
  "T"."STATUS" AS "STATUS", 
  "T"."PROJECT" AS "PROJECT", 
  "T"."DESCRIPTION" AS "DESCRIPTION", 
  "T"."ASSIGNEE" AS "ASSIGNEE", 
  "U"."FIRSTNAME" AS "FIRSTNAME", 
  "U"."LASTNAME" AS "LASTNAME", 
  "T"."TYPE" AS "TYPE"
FROM "ZBC_TASKS" "T" LEFT OUTER JOIN "ZBC_USERS" "U" ON ( 
  "T"."CLIENT" = "U"."CLIENT" AND 
  "T"."ASSIGNEE" = "U"."USER_ID" 
)