BWA, Exalytics and SAP-HANA

[former_member182313]

INTRODUCTION

Ever since SAP-HANA was announced couple of years back, I've been following the discussions/developments around In-Memory Database space. In Oct 2011, Oracle CEO Larry Ellison introduced Oracle Exalytics to compete with SAP-HANA. After reading white papers on both SAP-HANA and Oracle Exalytics, it was obvious they were different. The comparison of SAP-HANA and Oracle Exalytics is like comparing apples to oranges.

On May 8, 2012 I tweeted:

Not sure who 3 blogs' authors are addressing. Vishal Sikka addressing techs?why now?Most Techs already knew.nthg new

— Bala Prabahar (@praba01) May 8, 2012

SAP Mentor David Hull responded:

Perhaps most that are plugged in, as you are. But most I talk with haven't a clue as to the diff between the two.

— David Hull (@sapdba) May 8, 2012

I was a bit surprised to know that most don't have a clue as to the difference between Exalytics and SAP-HANA. The difference looked obvious to me. I realized either I was missing something or they were. So I decided to write this blog. And since this blog compares SAP products with Oracle products, I've decided to use Oracle DB instead of generic term RDBMS.

First I'll discuss the similarity between SAP-BW, Oracle-Exalytics and SAP-HANA. At a very high level, they look similar as shown in the picture below:

As shown, BW application sits on top of a database, Oracle or SAP-HANA. And the application helps the user find right data. The similarity ends there.

Let us now review how Oracle-Exalytics compares with SAP-BW with Business Warehouse Accelerator (BWA): As you can see below, there appears to be one-to-one match between the components of SAP-BW and Exalytics.

Steps	SAP-BW	Exalytics	Comments
1 and 1a	Data found in BWA; and returned to the user	Data found in Adaptive Data Mart & returned to the user
2 & 2a	Data found in OLAP Cache and returned to the user	Data found in Intelligent cache and returned to the user	This means data was not found in BWA or Adaptive Data Mart
3 & 3a	Data found in Aggregates and returned to the user	Data found in Essbase Cubes and returned to the user	This means data was not found in 1) Adaptive Data Mart or BWA and 2) OLAP Cache or Intelligent Cache
4 & 4a	Data found in Cubes and returned to the user		Not sure if Essbase supports aggregates; However Oracle supports materialized views;I assume this is similar to SAP-BW's aggregates.

The diagram below shows why Exalytics Vs SAP-HANA comparison is like apple to orange comparison. In Exalytics, the information users need gets pre-created at a certain level/granularity. One of the best practices in BW/DW world is to create the aggregates upfront to get acceptable response times.

In SAP-HANA, however, aggregates are created on the fly; data in SAP-HANA resides in raw form, and depending on what users need, the application performs the aggregation at runtime and displays the information on the user's screen. This helps the users perform analysis near real-time and more quickly.

Based on the diagrams shown above, Exalytics it seems is comparable to SAP's six year old BWA technology.

SUMMARY

Based on discussions above, the diagram below compares all three products SAP-BW with BWA, Exalytics and SAP-HANA.

                                           Note: I didn't connect Disk to HANA DB because it is primarily used for persistence.

I wanted to keep this blog simple so didn't include a lot of details. Depending on your questions/thoughts, I'm planning to either update this blog or write new blog.