Pentaho and HP Vertica – Big Data Analytics

Anyone going to the HP Vertica conference next week in Boston? (August 12, 2014)

If so, stop by and say Hi at the Pentaho booth in the expo center!

BTW, I uploaded a quick & short video that I threw together with no voiceover, but shows you how easy & quick it is to make a Dashboard in Pentaho 5.1 against a Big Data source like HP Vertica.

See it here.

HP Vertica is a world-class MPP Analytical Database and is a perfect match for Pentaho’s Analytics Suite. In the video you’ll see me through together a quick Dashboard by stacking Analyzer report components that are querying a Mondrian cube.

The business model is based on Vertica’s VMart data warehouse sample data and the semantic models is generated automatically through Pentaho’s auto modeler. I’m using our Web-based Thin Modeler to modify the model a bit before publishing it for ad-hoc interactive analysis.

Hope to see you @ the HP Vertica conference in Boston next week!  Best, Mark

Convert SSAS Snowflake Schemas to Pentaho Mondrian

Last weekend at a local tech conference, I was speaking to a few of my friends in the SQL Server & Microsoft BI consulting business about migrating cubes and BI solutions from SSAS to Pentaho using the Mondrian ROLAP engine with tools like ssas2mondrian. I explain different methods of starting over and generating new OLAP models using Pentaho’s auto modeler and Analyzer here and how to start with migrating simple SSAS cubes to Mondrian ROLAP schemas here.

So I felt like it would be a good challenge to see if I could convert a more complex SSAS cube to a Mondrian model that included Reference Dimensions in SSAS and convert those to a snowflake model in Mondrian using JOINs in dimension definitions.

Additionally, if your Microsoft BI solution is using Excel in SharePoint for visualizations (Excel is widely used for business intelligence), you will want to use the Pentaho visualizations to connect to the Mondrian ROLAP engine after migration. I think I’ve got this most of the way there, so I thought I’d kick it out in a blog post here.

The best way to begin the migration process is to use the ssas2mondrian utility that I put here on Box as a compiled EXE, or grab the source code on GITHUB and have at it. I would love to get some community additions to grow this migration capability.

The Adventure Works sample data set includes snowflake dimension designs, but I felt like working on a different data set this time. So I used the Mondrian sample Foodmart data set this time and made a simple cube in SSAS that included the dimension-to-dimension join to represent a snowflake schema with the Product Class dimension to Product dimension, along with Regular dimension relationships to fill-out just a simple, minimal cube:

After deploying that cube to the SSAS server, Microsoft BI consultants will want to put visualizations for end-users in Excel, SharePoint and SSRS that will look something like this:

This is a simple Excel representation of sales from the Foodmart fact table sliced up by Product Family, which is from a leaf-level dimension attribute coming from the Product Class dimension table, represented in SSAS as a Reference Attribute and as a snowflake join in Mondrian.

Now let’s convert that to Pentaho …

First, I’ll run the ssas2mondrian utility to build out the base model, which takes the online cube from my SSAS database and generates Mondrian schema XML file output which I’ll redirect to a local file on my filesystem from a Windows PowerShell (DOS prompt will work just fine, too):

Ok, let’s open this up and see what we get in PSW (Pentaho Schema Workbench):

Notice that ssas2mondrian has converted measure groups to virtual cubes (no support yet for measure groups in Mondrian 3.x), assumptions have been made about key columns for dimensions (you can’t have composite keys for dimensions in Mondrian 3.x), hierarchies were generated and physical cubes were generated from fact tables. Check the help (ssas2mondrian /help) in the utility for other options when migrating from SSAS to Mondrian.

To fix the red Xs in the schema, we need to clean-up a few things. In this case, PSW did not like the table names because Mondrian is a ROLAP engine and will issue SQL queries converted from MDX from a client tool. I did used SELECT statements from SSAS because I kept my Foodmart database in MySQL as the source for this SSAS schema. So I cleaned-up those names and removed a few levels in the hierarchies that didn’t make sense for these sample reports to get to a clean schema check:

That’s better. Now publish the Mondrian schema to your Pentaho Business Analytics server and you’re ready to start building Analyzer reports like this pie which is an OLAP query sending MDX to Mondrian using the snowflake join dimension of Product Family:

Let’s do a quick solution check: we’ve migrated the cube model from SSAS to Pentaho Mondrian, the report from Excel to Pentaho Analyzer and now let’s build a dashboard to replace SharePoint … For more info on building Pentaho Dashboards, check out this YouTube video.

There ya have it. Now, admittedly, I used a set of controlled samples that pretty much led me to a successful migration in a snowflake model. That begin said, I am hopeful that these instructions, the demo and the ssas2mondrian utility help to provide you with the means to get started with a migration.

BTW, I’ve posted the SSAS & Mondrian schemas here if you’d like to download them to play around with.

AdventureWorks DW on Pentaho, part 3: Geo Mapping AdventureWorks

In the previous parts of this series, I’ve showed you how to make quick, auto-modeled OLAP cubes and reports on a SQL Server AdventureWorks data warehouse as well as how to take your existing SSAS cubes on top of those SQL Server DWs and turn them into Mondrian cubes, which runs natively inside of the Pentaho Business Analytics suite.

Here in part 3, I am going to take the Analytics a step futher by using Geo Maps on top of the SQL Server Adventure Works data warehouse by modeling the ROLAP schema manually instead of with the Pentaho auto-modeler. And since I’m finally upgraded to the latest 5.0 version of the Pentaho Suite. you may notice a few UI differences and workflow changes in the process. To follow along, make sure you download the latest & greatest Pentaho 5.0 product here.

Instead of starting the analysis process from the Pentaho User Console or Analyzer, we will build a model first as an XML document and we’ll use the Pentaho cube design tool, Pentaho Schema Workbench:

You can download the complete sample XML schema that I built which you use in Pentaho Mondrian and Schema Workbench to connect to your SQL Server AdventureWorks Data Warehouse database to try this out on your own Pentaho Business Analytics suite. What I typically do when building a manual Mondrian schema is to start-up the Pentaho Schema Workbench (PSW) client and build out the primary parts of the model such as the measures, dimensions, calculations, etc. Then save the schema file as an XML file and edit it with an XML editor such as Visual Studio, Eclipse or Notepad++.

The reason why we are following this workflow for this example is do to the nature of the SQL Server sample data warehouse, Adventure Works (AW). AW makes use of a number of “snowflake” schema joins between dimension tables. The auto-modeler from Analyzer and PUC in Pentaho support only “star” schemas, so I write the model using PSW and manual XML to join the Customer dimension with the Geography dimension and the Customer key back to the customer key in the Fact table, which is FactInternetSales in this model. This will provide Analyzer with an MDX query to resolve the geography from the Fact table and graph it on the map using the hierarchy that I’ve defined below as Country, State, City, Postal Code:

<Dimension type=”StandardDimension” visible=”true” name=”Geo”>
<Hierarchy name=”default” visible=”true” hasAll=”true” primaryKey=”CustomerKey” primaryKeyTable=”c”>
<Join leftAlias=”c” leftKey=”GeographyKey” rightAlias=”g” rightKey=”GeographyKey”>
<Table name=”DimCustomer” schema=”dbo” alias=”c”>
</Table>
<Table name=”DimGeography” schema=”dbo” alias=”g”>
</Table>
</Join>
<Level name=”Country” visible=”true” table=”g” column=”CountryRegionCode” uniqueMembers=”false”>
</Level>
<Level name=”State” visible=”true” table=”g” column=”StateProvinceName” uniqueMembers=”false”>
</Level>
<Level name=”City” visible=”true” table=”g” column=”City” uniqueMembers=”false”>
</Level>
<Level name=”PostalCode” visible=”true” table=”g” column=”PostalCode” uniqueMembers=”false”>
</Level>
</Hierarchy>
</Dimension>

. . .

<Cube name=”SalesGeo” visible=”true” cache=”true” enabled=”true”>
<Table name=”FactInternetSales” schema=”dbo”>
</Table>
<DimensionUsage source=”Geo” name=”Geo” visible=”true” foreignKey=”CustomerKey”>
</DimensionUsage>
<Measure name=”TotalSales” column=”SalesAmount” datatype=”Numeric” aggregator=”sum” visible=”true”>
</Measure>
<Measure name=”NumOfCusts” column=”CustomerKey” aggregator=”distinct-count” visible=”true”>
</Measure>
</Cube>

Now that we have a functioning schema, publish it to the Pentaho BA Server either from Schema Workbench under File >> Publish, or through the Import mechanism in the Pentaho website. This will make the schema available to both the Mondrian ROLAP engine and to your report designers who are using Analyzer for OLAP queries and reports:

 

I’ll select the AWGeo model and now we’re in the familiar Pentaho Analyzer experience where I can grab the measures that I built in the model from AdventureWorks for total sales and distinct count of unique customers:

 

To put this into a Geo Map, I’ll remove the levels from the Geography dimension and leave just the top-level Country level as the Geo Dimension on the design surface. This way, we’ll drill-down from highest level down to finest grain in the map. Select Geo Map from the visualization drop-down menu at the top-right of the Analyzer screen … Now inside the map, I can drill to detail based on my 2 measures that are defining the circle size and color:

 

There ya have it … SQL Server 2012 data warehouse serving data to the Pentaho ROLAP engine (Mondrian) with a defined schema that models the Geography dimension for customers of Adventure Works with total sales and unique customers.

 

Migrate Adventure Works Sales Cubes from SSAS MOLAP to Mondrian ROLAP

In the 2 previous blog entries about recreating the SSAS example cubes for Adventure Works sales BI on Pentaho, I focused on generating new departmental-sized ROLAP cubes through the thin client Auto Modeler tools here & here.

In this entry, I’m going to show you how you can move over to the Pentaho BA Suite quickly by getting started with your existing SSAS cubes, such as the Adventure Works sales cubes, by migrating them pretty much as-is to the Pentaho ROLAP engine called Mondrian. This way, you can use the modeling tools that you are already familiar with (i.e. BIDS) and just convert them to Mondrian. Once you are converted over to the Pentaho platform, then you can start playing around with Pentaho analytics and manage the new version of the cubes in Pentaho.

In case you didn’t already do so, make sure you go here to download the evaluation of the Pentaho Business Suite here. And here is the Codeplex link for the open source download of the Adventure Works SSAS 2012 MOLAP cubes that we’ll use for this demonstration.

Make sure you also download the SQL Server 2012 JDBC driver and the tool that I built to help you migrate your online SSAS cubes from the SQL Server Analysis Server to Mondrian XML schema output files using AMO here, called SSAS2MONDRIAN. The full source code and C# project is available on GitHub in case you want to add more to it, have a look around, etc. The tool needs more features and error catching, so please contribute your ideas back to the source project!

So basically, instead of recreating a new OLAP model in Pentaho’s Analyzer, we are going to just migrate as-is from SSAS. Instead of rewriting the details of some of the primary differences between the 2 engines that you need to be aware of, I’m going to just link you back to my last posting on this topic at KromerBigData. You’ll need to become familiar with the Mondrian schema and MDX differences because we don’t have a complete migration tool that can do it all for you. Instead, the ssas2mondrian utility will take your model outline of dimensions, measures, expressions, attributes, hierarchies and  measure groups and convert them to Mondrian descriptors and names, but leaving out decisions about conflicts and conversion gaps in the hands of the BI developer.

Ok, once you’ve loaded the AdventureWorks 2012 DW database and the MOLAP cubes from Codeplex into SQL Server, you should see them appear in your SSMS:

 

Next, run the ssas2mondrian utility and redirect the output to an XML file so that we’ll be able to open the model in Pentaho Schema Workbench to make it ready for Mondrian:

You can see some of the output in that PowerShell screenshot above. I first ran the conversion utility without redirecting the output to a file, so some of the stdout is visible. I selected the server, cube, SSAS databsae and chose a new name for the resulting Mondrian schema, which is what will appear to report users when they build reports in Pentaho Analyzer.

Notice the conversion utility just using Console.WriteLine to output a Mondrian schema format. But, now I can open that schema file in Pentaho Schema Workbench (PSW) and work with it to clean things up and make it ready for Pentaho Analytics:

Make sure that you connect to the AdventureWorksDW2012 database from PSW as well under Database Connections. Remember that Mondrian is ROLAP only, so you will always send queries to the source database in Mondrian which will handle caching as well. Also take notice of the red check marks above. That means that you’ll want to open those nodes in the tree and look at the error in the bottom of the PSW screen. It is possible that some of the table names are actually named queries in the SSAS cube model, which means that those will need to become views in the source Adventure Works database to resolve the red check in PSW for Mondrian.

You can now use that ROLAP model to build Pentaho Analyzer reports and continue to maintain the models directly in Pentaho Mondrian, taking SSAS away from the solution. Or, if you like designing models in BIDS, build your cube there and then run ssas2mondrian to load the model into the Pentaho suite!

OPASS Discussions & Big Data in the Real World

If you are in the Orlando Sanford area tomorrow night (Thursday October 24 @ 6;30 register here) then come join the Orlando PASS gang where I will lead a discussion on Big Data and Big Data Analytics in the real world. I am basing this discussion on the systems that we designed and took to market for Razorfish and will include demos of HDInsight, Hadoop, NoSQL databases, Big Data Analytics with Pentaho and SQL Server. Here is the Slideshare link to the presentation for the meeting.

Adventure Works SQL DW on Pentaho OLAP, part 2

In Part 1, I built a very simple rudimentary OLAP model for reporting in Pentaho’s Business Analytics suite by pointing the Web-based auto modeling tool to my SQL Server Adventure Works data warehouse.

In part 2, I am going to show you how to use the OLAP Thin Modeler and Analyzer tool to modify that base auto-generated model and to create custom calculations from Adventure Works.

I’m going to start in the Pentaho User Console and I’m going to edit the model that was generated for AdventureWorks in Part 1 by selecting “Manage Existing”

In the subsequent Thin Model Editor screens, you will be able to do a number of operations on the cube model that you may be familiar with if you are developed SSAS cubes in the past and had to modify data source views, dimensions, measures, calculations, etc. What I am going to do is to take out some of the fields that will just cause confusion and noise for the end Analyzer user and to make sure that I have the proper formatting and properties set on the most important and common reporting fields in the model.

 

You may notice that the default auto-generated OLAP model contains Dimension Levels that may have been created with assumptions that don’t fit your business needs. This is where you will go in there to clean those up, modify hierarchies, etc. In my case, I renamed CalendarYear to just “Calendar” and dragged in Year, Quarter, Semester to build a hierarchy to aid users in navigating the data.

Now when a user builds Analyzer reports from my model, they will have a much cleaner logical model to work from. Make sure that you also use that last step to clean up names and make the entity names user-friendly with business entity desciptors, not database column names!

Next, create an Analyzer report from this new AdventureWorks cube model. I’ve dragged over UnitPrice as m measure into the pivot table and I’m going to slice the data my Model Name. But I also want to see the total per member of the total amount, which is Unit Price + Tax Amount. To do this, i made a custom measure from Analyzer with a right-click on the table header and enter this simple formula into the edit box: [UnitPrice] + [TaxAmt]”. Any valid MDX statement will work here to make calculated measures, i.e. ([Measures].[Unit Sales], Ancestor([Product].CurrentMember, [Product].[Product Family]))”.

 

And here’s what that looks like as a chart with a bar for the UnitPrice from the AventureWorks DW and my new OLAP Calculated Measure for Total Price:

 

Next up in the Part 3 finale of the series: We’ll take that cube model outside of the Analyzer / Auto Modeler realm and build it out even further and test it with our own MDX queries directly.

 

Adventure Works SQL DW on Pentaho OLAP, part 1

Let’s say you have SQL Server databases for your data marts and warehouses in your organization, but you are looking for alternatives to SSAS cubes and SharePoint-based dashboards. If you are like me and have built many BI solutions in SSAS OLAP and PPS, then you’ll find a transition to OSS with Pentaho to be very easy and a natural fit for those BI scenarios. We’re going to take this SQL Server 2012 DW and SSAS cube and recreate it all in Pentaho:

I’m going to kick this series off with a very simple BI dashboard using the traditional SQL Server Adventure Works data warehouse data set and put a Pentaho ROLAP cube and dashboard on top of that data. What I think you’ll really be impressed with is how much easier it is than building cubes in Visual Studio and PPS dashboards.

Start by going to Pentaho.com to download an evaluation version of the Pentaho Business Analytics suite and run the installer. We’re going to stay completely in a thin client browser experience for this demo, so no need to open any IDE tools through this entire workflow.

I’m using 4.8.2 of the Pentaho suite for this series and so when I log into the portal, I will use the Analysis feature to point to the SQL Server database and auto-generate the OLAP cube as well as design the visualizations. This is also where I can put my reports and analysis views together for end-user dashboards:

 

When you click to create new Analysis content, all you have to do to recreate a cube in the Pentaho Mondrian OLAP engine is to point to your DW database source and the engine will auto generate the model for you. So to replace the SSAS cube I have above, just follow the flow of these next 3 steps as I point to SQL Server, select my facts and dimension tables and create the star joins. This is a very simple beginning model which we will use for the rest of this series to build upon with custom calculations and other features. In classic AdventureWorks mode, I will name InternetSales as my fact table and let’s keep things simple and straightforward for this first intro to Pentaho modeling and just join in the Date and Product dimension tables. Just like SSAS, Mondrian will treat facts as measures and dimension tables as dimensional hierarchies and aggregation levels from your data warehouse. Much, much more on this in the coming weeks …

 

 

That’s all you have to do. Now you will select the model which will show up in your list as the name that you typed in from the screenshot above which I called simply “AdventureWorks”. Selecting that model will drop you into the interactive Analyzer reporting tool where you will see a field list to make pivot tables and data visualizations which you can see below. Think of that last step as running through the SSAS cube wizard in Visual Studio with data source views and publishing the cube on the SSAS server. This can be done in a much smaller number of steps here in Pentaho.

 

Remember that this is using ROLAP for the cube engine (Pentaho’s Mondrian), so in the upcoming parts of the series, I’ll talk about optimizing and customizing the logical OLAP models so that these reports can perform well for you. Your final step is to put your reports together as an interactive dashboard. In upcoming parts of the series, we’ll make the dashboard fully interactive as well. For now, just pick a couple of reports that you’ve generated from the AdventureWorks model and drop them onto the Dashboard Designer surface:

 

That’s pretty much it. We’ve recreated the OLAP cubes and reports and put them into a dashboard all in a browser using Pentaho with the SQL Server database source, replacing SSAS and SharePoint PPS. I know it was quick & brief, so think of this first part as just a teaser. We’ll continue to build this out with more features so that you can have some guidance when trying out Pentaho’s BI Suite.

As always, just reach out to me with any questions or requests. Enjoy! Br, Mark

FYI, if you need to download the SQL Server sample databases above, you can go here on Microsoft’s Codeplex site to get Adventureworks.