How to create Multi dimensional transformer cube in Microsoft power BI like cognos
as mention in below link
https://www.youtube.com/watch?v=d_rUNLJAUTU&list=PL1UFrxYya46MFZ3TFPpDOzR0WVMZo91gm
Any positive response will be appreciated
Thanks in advance.
I did not watch the video, but you cannot create cubes in Power BI as it is a reporting tool, not an OLAP engine like Cognos Transformer. Power BI is more equivalent to Cognos Workspace Advanced. Microsoft SQL Server Analytical Services (SSAS) is the Microsoft OLAP engine.
You can, however, use Power BI in an in-memory ROLAP like manner over a star schema using the Matrix visualization but unless data volumes are relatively small data load times can be excessive and you may run out of RAM. Direct queries get around the size limitation but can be slow unless you have a very powerful database server.
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I'm having a real hard time understanding what the difference is between a tabular vs multidimensional model.
Don't both use dimensions and fact tables?
Can't both have a star or snowflake schema?
Don't both have measures and calculated columns?
What is the difference?
Also, if I'm using Power BI and I connect to SQL Server instead of SSAS, I can still do my thing with it. Why is SSAS needed for tabular models if you can just do it in SQL Server?
Don't both use dimensions and fact tables?
Nope. Multidimensional uses Attribute Hierarchies and Measure Groups. Tabular uses Tables, and has no built-in notion of what a "fact" or "dimension" is.
Can't both have a star or snowflake schema?
Yes. And Tabular can have other designs as well. Tabular models can have single-table, or more normalized schemas, although using a star or snowflake design is generally considered a best-practice.
Don't both have measures and calculated columns?
MD does not have calculated columns. See Comparing tabular and multidimensional solutions
Also, if I'm using Power BI and I connect to SQL Server instead of SSAS, I can still do my thing with it.
Nope. Power BI always uses a Tabular or Multi-Dimensional model. When you connect to SQL Server with Power BI you are creating a Tabular model, and either Importing the data into memory, or creating a DirectQuery model (or a hybrid). In either case there is still a Tabular Model created, either embedded in the .PBIX or in a SSAS/AAS server.
I have been working on multidimensional analysis with pentaho community. The problem is, when I do the aggregations and filters, I get in the output no more than 1000 records(rows). I want to know if am doing something wrong or pentaho analysis tool has a limitation.
If so, does power BI community edition have a good limit ? Or can you suggest me another community tool to continue the work with it.
Are you using Saiku for OLAP analysis?
For Saiku, we have the limit in
TABLE_LAZY_SIZE = 1000 (default) Which you can change as per your requirement.
reference: http://saiku-documentation.readthedocs.io/en/latest/saiku_settings.html
Now we are on a process of converting few of our ssrs reports into Power BI. I wonder if there any option to import an entire report structure(rdl files) into power BI. please help me about this
Import of SSRS reports (.rdl) is supported now in Power BI premium.
This feature is called as Paginated Reports.
Refer https://learn.microsoft.com/en-us/power-bi/paginated-reports-save-to-power-bi-service
I understand this is very late reply, but I guess it could help someone.
There isn't. SSRS & Power BI are fundamentally different tools. If your SSRS reports are simple, then it shouldn't be hard to move the queries over to Power BI and then reproduce the same visuals (tables, charts, etc), though it would still look & feel very different.
Power BI has a focus on interactivity & data exploration that SSRS does not. As you convert reports, you'll likely want to update them to take advantage of features like slicers & cross-filtering & drill-downs.
On the other hand, SSRS has a lot of fine-tuning options that simply don't exist in Power BI (including an entire expression language). There are a lot of things you can do with SSRS that you can't easily recreate in Power BI (which is why a general conversion tool would be very difficult to write).
A super-delayed response, I realize, so I'm curious as to how your conversion project worked out.
I have read all those article about datawarehouse and olap.....however I have some question on it
I have created a datawarehouse using mysql and I also created an API which contain ad-hoc query to query from the datawarehouse, so is this API consider as ROLAP?
Is it possible to create own OLAP? If yes, how?
Usually data warehouse has normalized structure and DWH is not the same as ROLAP.
ROLAP it is technique used to modeling data. ROLAP is usually used for reporting. ROLAP is very good to make analytical query and you can use many reporting (BI) tools to easily build reports on you data.
It isn't necessary to write you own application to build reports. ROLAP (relational OLAP) it is when you model you data as "star" or "snowflake" using facts and dimension tables in traditional RDBMS. It star schemas also called "multidimensional cubes".
By OLAP often is meant MOLAP (multidimensional OLAP) - it's when you really store your data in multidimensional data structure in special data stores (not in RDBMS).
You shouldent create you own MOLAP e data storag- you should use alredy developed OLAP servers like MANDARIN, Pentaho Olap,Essbase, ORACLE EE database with OLAP option.
The confusion you are pointing out comes from the fact that peoples tend to use this term anywhere and in a wrong context.
OLAP applications are precisely defined by the OLAP council. These are applications that fullfill a bunch of requirements. You can read these requirements Here.
In big words, these are analytical oriented applications that allow you to build reports in an a multidimensional fashion (it means you have dimensions and indicators that you can cross) and get fast anwsers at enterprise-scale, with drill down and drill accross capabilities. Something close to OLAP applications is this : http://try.meteorite.bi/
Building an adhoc reporting engine on top of a datawarehouse doesn't mean you have an OLAP application. Does it have a multidimensional shape ? Is it user oriented ? Is it fast enough ? It has to answer yes to all these questions and the ones below to be a candidate to be an OLAP application.
I have Essbase as the BI solution (for Predictive Analytics and Data Mining) in my current workplace. It's a really clunky tool, hard to configure and slow to use. We're looking at alternatives. Any pointers as to where I can start at?
Is Microsoft Analysis Services an option I can look at? SAS or any others?
Essbase focus and strenght is in the information management space, not in predictive analytics and data mining.
The top players (and expensive ones) in this space are SAS (with Enterprise Miner & Enteprise Guide combination) and IBM with SPSS.
Microsoft SSAS (Analysis Services) is a lot less expensive (it's included with some SQL Server versions) and has good Data Mining capabilities but is more limited in the OR (operations research) and Econometrics/Statistics space.
Also, you could use R, an open source alternative, that is increasing its popularity and capabilities over time, for example some strong BI players (SAP, Microstrategy, Tableau, etc.) are developing R integration for predictive analytics and data mining.
Check www.kpionline.com , is a product cloud based in Artus.
It has many dashboards, scenarios and functions prebuilt to do analysis.
Other tool than you could check is microstrategy. It has many functions to analysis.