--- title: Learn SAP from the Experts | The SAP PRESS Blog | Renzo Colle, Ralf Dentzer, and Jan Hrastnik description: Renzo Colle is currently responsible for the end-to-end programming model of SAP S/4HANA in the central architecture group. Ralf Dentzer has been working for several years in the central architecture group of the SAP S/4HANA suite with a focus on the use of core data services in SAP S/4HANA. Jan Hrastnik is a member of the SAP S/4HANA cross architecture team, where he focuses on the virtual data model and the use of core data services in ABAP applications. --- [![rheinwerk-sappress-logo-header-1](https://blog.sap-press.com/hubfs/rheinwerk-sappress-logo-header-1.svg)](https://blog.sap-press.com/) [Blog](https://blog.sap-press.com) - Books - Get an overview of our books and courses on every relevant SAP topic. - [Programming](https://sap-press.com/programming/) - [Administration](https://sap-press.com/administration/) - [BI](https://sap-press.com/business-intelligence/) - [Finance](https://sap-press.com/finance-controlling/) - [Logistics](https://sap-press.com/logistics/) - [HR](https://sap-press.com/human-resources/) - [CRM & Sales](https://sap-press.com/marketing-sales/) - [HANA](https://sap-press.com/hana/) - [Introductions](https://sap-press.com/introductions/) - [E-Bites](https://sap-press.com/e-bites/) - [Certification Guides](https://www.sap-press.com/certification-guides/) - [Rheinwerk Courses](https://www.sap-press.com/online-courses/) - Book Subscription - Get unlimited access to all SAP PRESS books! - [SAP PRESS Subscription](https://sap-press.com/subscriptions/) ![](https://blog.sap-press.com/hs-fs/hubfs/What%20Is%20SAPs%20Generative%20AI%20Hub_.jpg?width=1000&name=What%20Is%20SAPs%20Generative%20AI%20Hub_.jpg) [Programming](https://blog.sap-press.com/tag/programming) | Featured article ## [What Is SAP's Generative AI Hub?](https://blog.sap-press.com/what-is-saps-generative-ai-hub) Every agent you build on SAP Business AI eventually has to call a large language model, and the generative AI hub is where that call gets routed, secured, and paid for. ![SAP PRESS](https://blog.sap-press.com/hubfs/Twitter_profile_pic.svg) by [SAP PRESS](https://blog.sap-press.com/author/sap-press) [Read More](https://blog.sap-press.com/what-is-saps-generative-ai-hub) ![Renzo Colle, Ralf Dentzer, and Jan Hrastnik](https://blog.sap-press.com/hubfs/Renzo%20Colle%2c%20Ralf%20Dentzer%2c%20and%20Jan%20Hrastnik-1.png) **Renzo Colle, Ralf Dentzer, and Jan Hrastnik** Renzo Colle is currently responsible for the end-to-end programming model of SAP S/4HANA in the central architecture group. Ralf Dentzer has been working for several years in the central architecture group of the SAP S/4HANA suite with a focus on the use of core data services in SAP S/4HANA. Jan Hrastnik is a member of the SAP S/4HANA cross architecture team, where he focuses on the virtual data model and the use of core data services in ABAP applications. # Blogs by Renzo Colle, Ralf Dentzer, and Jan Hrastnik [![ABAP CDS Q&A with Authors Renzo Colle, Ralf Dentzer, and Jan Hrastnik](https://blog.sap-press.com/hs-fs/hubfs/ABAP%20CDS%20Q%26A%20with%20Authors%20Renzo%20Colle%2c%20Ralf%20Dentzer%2c%20and%20Jan%20Hrastnik.png?height=600&name=ABAP%20CDS%20Q&A%20with%20Authors%20Renzo%20Colle,%20Ralf%20Dentzer,%20and%20Jan%20Hrastnik.png)](https://blog.sap-press.com/abap-cds-qa-with-authors-renzo-colle-ralf-dentzer-and-jan-hrastnik) [Programming](https://blog.sap-press.com/tag/programming) ## [ABAP CDS Q&A with Authors Renzo Colle, Ralf Dentzer, and Jan Hrastnik](https://blog.sap-press.com/abap-cds-qa-with-authors-renzo-colle-ralf-dentzer-and-jan-hrastnik) Authors Renzo Colle, Ralf Dentzer, and Jan Hrastnik recently took part in the SAP PRESS Book Club webinar series, where they answered reader... ![Renzo Colle, Ralf Dentzer, and Jan Hrastnik](https://blog.sap-press.com/hubfs/Renzo%20Colle%2c%20Ralf%20Dentzer%2c%20and%20Jan%20Hrastnik-1.png) by [Renzo Colle, Ralf Dentzer, and Jan Hrastnik](https://blog.sap-press.com/author/renzo-colle-ralf-dentzer-and-jan-hrastnik) [Read More](https://blog.sap-press.com/abap-cds-qa-with-authors-renzo-colle-ralf-dentzer-and-jan-hrastnik) ### SAP Blog Topics - [All SAP Topics](https://blog.sap-press.com) - [Logistics](https://blog.sap-press.com/tag/logistics) - [Programming](https://blog.sap-press.com/tag/programming) - [FICO](https://blog.sap-press.com/tag/fico) - [Administration](https://blog.sap-press.com/tag/administration) - [Featured](https://blog.sap-press.com/tag/featured) - [Business Intelligence](https://blog.sap-press.com/tag/business-intelligence) - [What Is?](https://blog.sap-press.com/tag/what-is) - [CRM & Sales](https://blog.sap-press.com/tag/crm-sales) - [Human Resources](https://blog.sap-press.com/tag/human-resources) - [Video](https://blog.sap-press.com/tag/video) **Subscribe to our blog!**Get notified about future blog updates. - - - - - ### Most Popular Blog Posts 1. 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