© Ctac - Better Business. Ctac Cloud

SITNL 2016

What a CDS-view can do for You

Practical use of CDS Views on ECC EHP7 on HANA -

tricks & tips

Ben Meijs

© Ctac - Better Business. Ctac Cloud 2

ABOUT ME

© Ctac - Better Business. Ctac Cloud 3

Pictogram

CDS Quick RECAP

PictogramPictogram

Use Case – BW Extract

PictogramPictogram

Unit Conversions

PictogramPictogram

Date defaults/ functions

PictogramPictogram

Use Case – Report

PictogramPictogram

Texts in one go

Pictogram

Pictogram

Tips

PictogramPictogram

Outlook

Pictogram

© Ctac - Better Business. Ctac Cloud 4

What is a CDS?

© Ctac - Better Business. Ctac Cloud 6

Core Data Services – it’s an ABAPPER thing!

• Just like defining an Database View in SE11, but with a lot more options:

• INNER and OUTER JOINS

• ASSOCIATIONS

• UNION

• Built-in functions

• Parameters

• Annotations => DB-viewname, client dependency, buffering. generating Odata-services and BOPF-artifacts

• How do you define a CDS View?

• In ECLIPSE!

• Using a Data Definition Language

• Generates a Database View

• You use a CDS-view

• With Open SQL

• In other CDS-view

© Ctac - Better Business. Ctac Cloud 7

Creating a CDS with a JOIN - example

© Ctac - Better Business. Ctac Cloud 8

CDS – options and Built-in functions

© Ctac - Better Business. Ctac Cloud 9

CDS – options and Built-in functions

© Ctac - Better Business. Ctac Cloud 10

Creating a CDS with a JOIN - example

© Ctac - Better Business. Ctac Cloud 11

Pictogram

CDS Quick RECAP

PictogramPictogram

Use Case – BW Extract

PictogramPictogram

Unit Conversions

PictogramPictogram

Date defaults/ functions

PictogramPictogram

Use Case – Report

PictogramPictogram

Texts in one go

Pictogram

Pictogram

Tips

PictogramPictogram

Outlook

Pictogram

© Ctac - Better Business. Ctac Cloud 12

Use Case – CDS view for BW extractor without using any ABAP

Question: is it possible to define a fast BW extractor in an ECC-on-HANA environment, without any ABAP-statement?

• Selection of sales orders, purchase orders, inbound and outbound deliveries within a timeframe of next 6 weeks;

• Quantities in base unit of measure (MARA-MEINS);

• Aggregate this data on Material Number, Plant, Week number;

• Make it as fast as possible;

Technical Challenges:

• Material Unit conversion (every quantity in base unit of measure MARA-MEINS);

• No system variables in CDS on WAS740;

• No calculations possible with date fields in CDS-context on WAS740;

Answer: Yes, it is possible. A weekly run including all the necessary steps on BW now only takes a few minutes

© Ctac - Better Business. Ctac Cloud 13

Pictogram

CDS Quick RECAP

PictogramPictogram

Use Case – BW Extract

PictogramPictogram

Unit Conversions

PictogramPictogram

Date defaults/ functions

PictogramPictogram

Use Case – Report

PictogramPictogram

Texts in one go

Pictogram

Pictogram

Tips

PictogramPictogram

Outlook

Pictogram

© Ctac - Better Business. Ctac Cloud 14

Trick 1 - Unit Conversion using CDS

Option 1 – Use the ABAP function for material unit conversions

Option 2 – Let BW do the unit conversions

Option 3 – Include Material Conversion Table MARM in the CDS

© Ctac - Better Business. Ctac Cloud 15

Pictogram

CDS Quick RECAP

PictogramPictogram

Use Case – BW Extract

PictogramPictogram

Unit Conversions

PictogramPictogram

Date defaults/ functions

PictogramPictogram

Use Case – Report

PictogramPictogram

Texts in one go

Pictogram

Pictogram

Tips

PictogramPictogram

Outlook

Pictogram

© Ctac - Better Business. Ctac Cloud 16

Trick 2 – Default Date and Date +/+ 42 days

Option 1 – Use of two view parameters for these two dates

Option 2 – Use HANA: M_TIME_DIMENSION via an External view

© Ctac - Better Business. Ctac Cloud 17

Trick 3 – Get week number for date

Option 1 – Use of ABAP calendar function to calculate week numbers

Option 2 – Use HANA: M_TIME_DIMENSION via an External view

© Ctac - Better Business. Ctac Cloud 18

Snapshot of resulting CDS

Main CDS (extraction)

CDS – Open Deliveries

SUM group by MATNR/WERKS/WEEKNR

CDS – Open Deliveries

Details from VBBE

CDS – Time (Weeknumbers)

Weeknumber, based on VBBE-MBDAT

Stock

Shipments

Open Orders

© Ctac - Better Business. Ctac Cloud 19

Pictogram

CDS Quick RECAP

PictogramPictogram

Use Case – BW Extract

PictogramPictogram

Unit Conversions

PictogramPictogram

Date defaults/ functions

PictogramPictogram

Use Case – Report

PictogramPictogram

Texts in one go

Pictogram

Pictogram

Tips

PictogramPictogram

Outlook

Pictogram

© Ctac - Better Business. Ctac Cloud 20

Use Case – Just a simple ABAP Report

Question: Is it possible to read the first line of a ‘SAPscript’ text using a CDS-view?

• Selection of Sales order data with partners and status information

• The user wants the first line of a specific Sales order text in the output

Technical Challenges:

• How to get the first line of the text

• How to read a field of type LRAW (STXL-CLUSTD)

• Vague error messages

Solution

• Extra CDS-views needed in order to be able to read the first line of a text

• All primary key fields of all JOINED tables must be specified in the field list. Otherwise a DB-view is generated with all fields as key field. LRAW-fields cannot be key fields!

• The text can be converted in the ABAP ALV report using a specific IMPORT statement that converts from RAW to Text format.

Answer: Yes, if the implicit View key is generated correctly.

© Ctac - Better Business. Ctac Cloud 21

CDS-view with first line of long text

© Ctac - Better Business. Ctac Cloud 22

ABAP - Converting the LRAW text to readable format

© Ctac - Better Business. Ctac Cloud 23

Pictogram

CDS Quick RECAP

PictogramPictogram

Use Case – BW Extract

PictogramPictogram

Unit Conversions

PictogramPictogram

Date defaults/ functions

PictogramPictogram

Use Case – Report

PictogramPictogram

Texts in one go

Pictogram

Pictogram

Tips

PictogramPictogram

Outlook

Pictogram

© Ctac - Better Business. Ctac Cloud 24

Tips

How and when to use CDS-views:

• CDS offers options to limit number of needed ABAP-statements (Code Pushdown)

• Limit use of WHERE-clause in CDS-views (reusability!);

• CDS has more options than Open SQL

• Important role of CDS in SAP Architecture

Be careful and precise when using JOINS:

• Are you sure that you should use an INNER JOIN?

• Are you sure that you should use an OUTER JOIN?

• Did you specify all relevant JOIN fields in the ON-clause?

• Don’t forget the DISTINCT option of the SELECT-statement

Technical tips:

• CDS not limited to HANA

• If not all key fields of joined tables are specified in field list, all fields are considered key field in the generated VIEW

• External Views: synchronize and re-activate usage

© Ctac - Better Business. Ctac Cloud 25

Pictogram

CDS Quick RECAP

PictogramPictogram

Use Case – BW Extract

PictogramPictogram

Unit Conversions

PictogramPictogram

Date defaults/ functions

PictogramPictogram

Use Case – Report

PictogramPictogram

Texts in one go

Pictogram

Pictogram

Tips

PictogramPictogram

Outlook

Pictogram

© Ctac - Better Business. Ctac Cloud 26

Outlook – CDS as common data model in S/4HANA

© Ctac - Better Business. Ctac Cloud 27

Outlook – CDS as central model in future developments

© Ctac - Better Business. Ctac Cloud 28

© Ctac - Better Business. Ctac Cloud 29

Outlook – CDS as central model in future developments

© Ctac - Better Business. Ctac Cloud 30

© Ctac - Better Business. Ctac Cloud

Thank you