SAP ABAP CDS (Core Data Services)

Related Skills

sap-abap: Use for ABAP programming patterns used with CDS or when implementing EML statements in ABAP
sap-btp-cloud-platform: Use for CDS deployment scenarios on BTP or ABAP Environment configurations
sap-fiori-tools: Use when building Fiori Elements applications that consume CDS views or working with UI annotations
sap-cap-capire: Use for comparing CDS syntax between ABAP and CAP or when integrating ABAP CDS with CAP services
sap-api-style: Use when documenting CDS-based OData services or following API documentation standards

Quick Reference: https://help.sap.com/doc/abapdocu_cp_index_htm/CLOUD/en-US/abencds.html | SAP Cheat Sheets: https://github.com/SAP-samples/abap-cheat-sheets/blob/main/15_CDS_View_Entities.md

1. CDS View Fundamentals
2. Essential Annotations
3. Expressions and Operations
4. Built-in Functions
5. Joins
6. Associations
7. Input Parameters
8. Aggregate Expressions
9. Access Control (DCL)
10. Data Retrieval from ABAP
11. Common Errors and Solutions
12. Useful Transactions and Tables
Bundled Resources
Source Documentation

1. CDS View Fundamentals

View Types

Type	Syntax	Database View	Since
CDS View	`DEFINE VIEW`	Yes	7.4 SP8
CDS View Entity	`DEFINE VIEW ENTITY`	No	7.55

Recommendation: Use CDS View Entities for new development.

Basic CDS View Syntax

@AbapCatalog.sqlViewName: 'ZCDS_EXAMPLE_V'
@AbapCatalog.compiler.CompareFilter: true
@AccessControl.authorizationCheck: #NOT_REQUIRED
@EndUserText.label: 'Example CDS View'

define view ZCDS_EXAMPLE
  as select from db_table as t
{
  key t.field1,
      t.field2,
      t.field3 as AliasName
}

CDS View Entity Syntax (7.55+)

@AccessControl.authorizationCheck: #NOT_REQUIRED
@EndUserText.label: 'Example View Entity'

define view entity Z_CDS_EXAMPLE
  as select from db_table as t
{
  key t.field1,
      t.field2,
      t.field3 as AliasName
}

Key Difference: View entities omit @AbapCatalog.sqlViewName - no SQL view generated.

Eclipse ADT Setup

File → New → Other → Core Data Services → Data Definition
Enter name, description, and package
Select template (view, view entity, etc.)

2. Essential Annotations

Core Annotations

Essential annotations for CDS development:

@AbapCatalog.sqlViewName - SQL view name (max 16 chars)
@AbapCatalog.compiler.CompareFilter - Optimize WHERE clauses
@AccessControl.authorizationCheck - Set to #NOT_REQUIRED, #CHECK, #MANDATORY, or #NOT_ALLOWED
@EndUserText.label - User-facing description
@Metadata.allowExtensions - Allow view extensions

Complete Reference: See references/annotations-reference.md for 50+ annotations with examples.

Semantics Annotations (Currency/Quantity)

Required for CURR and QUAN data types to avoid error SD_CDS_ENTITY105:

-- Currency fields
@Semantics.currencyCode: true
waers,
@Semantics.amount.currencyCode: 'waers'
amount,

-- Quantity fields
@Semantics.unitOfMeasure: true
meins,
@Semantics.quantity.unitOfMeasure: 'meins'
quantity

UI Annotations (Fiori Elements)

@UI.lineItem: [{ position: 10 }]
@UI.identification: [{ position: 10 }]
@UI.selectionField: [{ position: 10 }]
field1,

@UI.hidden: true
internal_field

Consumption Annotations (Value Help)

@Consumption.valueHelpDefinition: [{
  entity: { name: 'I_Currency', element: 'Currency' }
}]
waers

For complete annotation reference, see references/annotations-reference.md.

3. Expressions and Operations

CASE Expressions

Simple CASE (single variable comparison):

case status
  when 'A' then 'Active'
  when 'I' then 'Inactive'
  else 'Unknown'
end as StatusText

Searched CASE (multiple conditions):

case
  when amount > 1000 then 'High'
  when amount > 100 then 'Medium'
  else 'Low'
end as AmountCategory

Comparison Operators

Standard operators: =, <>, <, >, <=, >= Special operators: BETWEEN x AND y, LIKE, IS NULL, IS NOT NULL

Complete Reference: See references/expressions-reference.md for all operators and expressions.

Arithmetic Operations

quantity * price as TotalAmount,
amount / 100 as Percentage,
-amount as NegatedAmount

Session Variables

Available system variables (SY fields equivalent):

$session.user (SY-UNAME) - Current user
$session.client (SY-MANDT) - Client
$session.system_language (SY-LANGU) - Language
$session.system_date (SY-DATUM) - Current date

Complete Reference: See references/expressions-reference.md for all system variables.

$session.user as CurrentUser,
$session.system_date as Today

4. Built-in Functions

CDS provides comprehensive built-in functions for string, numeric, and date operations.

Key Function Categories

String Functions: concat(), length(), substring(), upper(), lower(), replace()
Numeric Functions: abs(), ceil(), floor(), round(), division()
Date Functions: dats_add_days(), dats_add_months(), dats_days_between()
CAST Expression: Convert between ABAP data types

Complete Reference: See references/functions-reference.md for all 50+ functions with examples.

Quick Examples

-- String operations
concat(first_name, last_name) as FullName,
upper(name) as UpperName,
substring(description, 1, 10) as ShortDesc

-- Numeric operations  
abs(amount) as AbsoluteAmount,
round(value, 2) as RoundedValue,
division(10, 3, 2) as PreciseDivision

-- Date operations
dats_add_days(current_date, 7) as NextWeek,
dats_days_between(start_date, end_date) as Duration

-- Type conversion
cast(field as abap.char(10)) as TextField,
cast(amount as abap.curr(15,2)) as CurrencyField

**ABAP Types**: `abap.char()`, `abap.numc()`, `abap.int4`, `abap.dats`, `abap.tims`, `abap.curr()`, `abap.cuky`, `abap.quan()`, `abap.unit()`

---

## 5. Joins

### Join Types
```sql
-- INNER JOIN (matching rows only)
inner join makt as t on m.matnr = t.matnr

-- LEFT OUTER JOIN (all from left, matching from right)
left outer join marc as c on m.matnr = c.matnr

-- RIGHT OUTER JOIN (all from right, matching from left)
right outer join mvke as v on m.matnr = v.matnr

-- CROSS JOIN (cartesian product)
cross join t001 as co

6. Associations

Associations define relationships between entities (join-on-demand):

Defining Associations

define view Z_ASSOC_EXAMPLE as select from scarr as c
  association [1..*] to spfli as _Flights
    on $projection.carrid = _Flights.carrid
  association [0..1] to sairport as _Airport
    on $projection.hub = _Airport.id
{
  key c.carrid,
      c.carrname,
      c.hub,

      // Expose associations
      _Flights,
      _Airport
}

Cardinality Notation

Syntax mapping:

[0..1] or [1] → association to one (LEFT OUTER MANY TO ONE)
[1..1] → association to one (exact match)
[0..*] or [*] → association to many (LEFT OUTER MANY TO MANY)
[1..*] → association to many (one or more)

Complete Reference: See references/associations-reference.md for detailed cardinality guide.

New Cardinality Syntax (Release 2302+)

association to one _Customer on ...   -- [0..1]
association to many _Items on ...      -- [0..*]

Using Associations

-- Expose for consumer use
_Customer,

-- Ad-hoc field access (triggers join)
_Customer.name as CustomerName

Path Expressions with Filter

-- Filter with cardinality indicator
_Items[1: Status = 'A'].ItemNo

For complete association reference, see references/associations-reference.md.

7. Input Parameters

Defining Parameters

define view Z_PARAM_EXAMPLE
  with parameters
    p_date_from : dats,
    p_date_to   : dats,
    @Environment.systemField: #SYSTEM_LANGUAGE
    p_langu     : spras
  as select from vbak as v
{
  key v.vbeln,
      v.erdat,
      v.erzet
}
where v.erdat between :p_date_from and :p_date_to

Parameter Reference

Use colon notation :p_date_from or $parameters.p_date_from

Calling from ABAP:

SELECT * FROM z_param_example(
  p_date_from = '20240101',
  p_date_to   = '20241231',
  p_langu     = @sy-langu
) INTO TABLE @DATA(lt_result).

8. Aggregate Expressions

Aggregate Functions

define view Z_AGG_EXAMPLE as select from vbap as i
{
  i.vbeln,
  sum(i.netwr) as TotalAmount,
  avg(i.netwr) as AvgAmount,
  max(i.netwr) as MaxAmount,
  min(i.netwr) as MinAmount,
  count(*) as ItemCount
}
group by i.vbeln
having sum(i.netwr) > 1000

9. Access Control (DCL)

Basic DCL Structure

@MappingRole: true
define role Z_CDS_EXAMPLE_DCL {
  grant select on Z_CDS_EXAMPLE
    where (bukrs) = aspect pfcg_auth(F_BKPF_BUK, BUKRS, ACTVT = '03');
}

Authorization Check Options

Available values:

#NOT_REQUIRED - No authorization check
#CHECK - Warning if no DCL exists
#MANDATORY - Error if no DCL exists
#NOT_ALLOWED - DCL ignored if exists

Complete Reference: See references/access-control-reference.md for detailed DCL patterns.

Condition Types

PFCG Authorization: where (field) = aspect pfcg_auth(AUTH_OBJECT, AUTH_FIELD, ACTVT = '03')

Literal Condition: where status <> 'DELETED'

User Aspect: where created_by ?= aspect user

Combined: where (bukrs) = aspect pfcg_auth(...) and status = 'ACTIVE'

For complete access control reference, see references/access-control-reference.md.

10. Data Retrieval from ABAP

Standard SELECT

SELECT * FROM zcds_example
  WHERE field1 = @lv_value
  INTO TABLE @DATA(lt_result).

SALV IDA (Integrated Data Access)

cl_salv_gui_table_ida=>create_for_cds_view(
  CONV #( 'ZCDS_EXAMPLE' )
)->fullscreen( )->display( ).

11. Common Errors and Solutions

SD_CDS_ENTITY105: Missing Reference Information

Problem: CURR/QUAN fields without reference

Solution: Add semantics annotations

@Semantics.currencyCode: true
waers,
@Semantics.amount.currencyCode: 'waers'
netwr

Or import currency from related table:

inner join t001 as c on ...
{
  c.waers,
  @Semantics.amount.currencyCode: 'waers'
  v.amount
}

Cardinality Warnings

Problem: Cardinality doesn't match actual data

Solution: Define cardinality matching data model

association [0..1] to ...  -- Use for optional relationships
association [1..*] to ...  -- Use for required one-to-many

For complete troubleshooting guide, see references/troubleshooting.md.

12. Useful Transactions and Tables

Key Transactions

SDDLAR - Display/repair DDL structures
RSRTS_ODP_DIS - TransientProvider preview
RSRTS_QUERY_CHECK - CDS query metadata validation
SE63 - Translation (EndUserText)
SE11 - ABAP Dictionary
SU21 - Authorization objects

Important Tables

DDHEADANNO - Header-level annotations
CDSVIEWANNOPOS - CDS view header annotations
CDS_FIELD_ANNOTATION - Field-level annotations
ABDOC_CDS_ANNOS - SAP annotation definitions

API Class

CL_DD_DDL_ANNOTATION_SERVICE - Programmatic annotation access:

get_annos() - Get all annotations
get_label_4_element() - Get @EndUserText.label

Bundled Resources

Reference Documentation

For detailed guidance, see the reference files in references/:

annotations-reference.md - Complete annotation catalog
functions-reference.md - All built-in functions with examples
associations-reference.md - Associations and cardinality guide
access-control-reference.md - DCL and authorization patterns
expressions-reference.md - Expressions and operators
troubleshooting.md - Common errors and solutions

Templates

For templates, see templates/:

basic-view.md - Standard CDS view template
parameterized-view.md - View with input parameters
dcl-template.md - Access control definition

Source Documentation

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Last Verified: 2025-11-23

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