There is an embedded version of BW available as of NetWeaver 7.0. This means for any SAP NetWeaver based system like ECC 6.0, CRM 7.0, SCM, Solution Manager including SAP Business Suite and S4/HANA there is a BW available inside.
Primarily the embedded BW shall be used within scenarios that are implemented in host system (ECC, CRM etc.) like embedded reporting scenarios (by leveraging BW's Analytic Manager (OLAP engine)) or embedded planning processes (leveraging BW's planning engine) however it is still full blown BW system. As per SAP they do not advise to use it as enterprise data warehouse.
Below are restrictions that are given by SAP while using the embedded BW:
1. Amount of data - shall not exceed 20% of total data volume in the system. If this happens there is probably a negative impact on core system functions.
2. Licenses – you may require license to run embedded BW in your NetWeaver system.
3. Security - it uses different authorization concept (BW one over classic concept used in ECC)
How to enable the embedded BW? Couple of activities shall be done in order to make the embedded BW work. This includes:
Assign Logical System Client – table RSADMINA
Set BW Namespaces to Modifiable - /BI0/* and /BIC/*
Activation of technical content
Switch On Business Function
1972819 - Setup SAP BPC optimized for S/4 HANA Finance and Embedded BW Reporting (aka Integrated Business Planning for Finance)
1919631 - Activating the BPC embedded