Can anyone provide me with some resources to learn the differences in calculating measures/dimensions using DAX in power BI when using a live connection to the data source? There appears to be some differences in how to calculate with the live connection vs importing a data set and I am interested to learn more on this topic.
Thank you!
For example, I cannot use datediff on the live SSAS connection.
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Is there a tool to synchronise an Oracle and a Grakn database in real time? I couldn't find any information online so any help would be greatly appreciated.
I know Grakn offers GRPC through its client drivers which I'm assuming is the way to go to push things into Grakn.
And I'm aware there are triggers in the Oracle tables, but not sure if will slow down the application layer on the Oracle DB. How would this impact the performance of the BD?
Thanks!
There aren't any such tools that you can use OOTB. If you need to keep the Oracle system running then I think you've got two options:
Intercept the data as it comes in and dispatch to both Oracle and Grakn.
Find a triggering mechanism, and as you outline, read from Oracle and push the data to Grakn through its driver(s).
GRPC is built in to Grakn's drivers, and is the only way to communicate with a Grakn server. These drivers are optimised as such!
i want data intregration part do with the help of Talend and other reporting, dashboard work will do in microstrategy. How can i connect them ?
is any odbc or any kind of process is possible ?
As i understand you want to integrate an ETL tool (Talend) to adecuate data for presentation, the only thing that does not sound to clear for me it's why you have interest in integrate them.
They are two process apart, so you can take the processed data thru the ETL tool (Talend or whatever other tool) to a db and that be the source of the BI tool you prefer.
Regards,
Alejandro
I have a question about mongodb. Indeed, I want to switch from oracle dbs to a mongo db in order to have more flexible structure. The goal of my project consists in carrying out some consistent data analysis after implementing a mongoDB which will able to store my data in json format for instance or some useful logs about requests done by my colleagues on a Web service.
Please, what are your tips ? What are the most efficient java frameworks in order to build a solid database ? Need I to learn some other languages ?
Feel free to suggest or to give me our advice on who to start properly with this tool. Any share of your feedback on your experiences with data analytics for BI will be a real pleasure for me.
Thanks... :)
I want to ask what are the performance gains of pulling reports in Sharepoint 2010 directly from an Oracle DW using an ODBC Connection as opposed to building an OLAP Layer using SSAS and accessing the data that way.
It sounds like you're confusing terminologies and technologies. Comparing ODBC to OLAP and SSAS is like comparing apples to oranges. They are very different things used for very different purposes. The commonality is that they both deal with data... and apples and oranges are both fruit.
But, trying to read between the lines, OLAP, if configured correctly, will deliver actionable information (biz intel etc.) much more quickly and readily than data aggregated from a standard RDBMS. After all, that's what OLAP is designed for:
In computing, online analytical processing, or OLAP (play /ˈoʊlæp/),
is an approach to swiftly answer multi-dimensional analytical (MDA)
queries.1 OLAP is part of the broader category of business
intelligence, which also encompasses relational reporting and data
mining.[2]
Now that SQL Server 2012 is released, you may want to look into building a BISM (using SSAS) over your Oracle data and then displaying the results in SharePoint.
Although you can use the 'PowerPivot on SharePoint' mode to be able to host (render) the BISM using SharePoint resources, you'd rather get a separate server to host SSAS, so that effort of rendering (presumably) large reports doesn't slow down your SharePoint server.
Of course it is still possible build an OLAP cube using SSAS, but unless you need one or more of the features not yet available in the BISM model, you'd rather just build a BISM than an OLAP cube, as the BISM leverages Vertipaq (so it's simpler to build, i.e. requires less ETL from Oracle). For more check out my deck on slideshare on the BISM
We have a client that has Oracle Standard, and a project that would be ten times easier addressed using OLAP. However, Oracle only supports OLAP in the Enterprise version.
Migration to enterprise is not possible
I'm thinking of doing some manual simulation of OLAP, creating relational tables to simulate the technology.
Do you know of some other way I could do this? Maybe an open-source tool for OLAP? Any ideas?
You can simulate OLAP functionality using client side tools pointed at a relational database.
Personally I think the best tool for the job is probably Tableau Desktop. This is an amazingly sophisticated front end analytics tool that will make your relational data look multidimensional without much effort, and the tool itself is really mind blowing. They have a free trial so you can take it for a spin. We use Tableau heavily for our own analysis and have been very impressed. Of course, this tool also works with multidimensional databases as well, so if you end up with some cubes at the end of the day you can continue to use the Tableau front end.
As for open source, you could try out Palo - an open source MOLAP server and Excel front end.
If you are interesting in building your own reporting front end and use .NET there are a number of components (such as the DevExpress PivotGrid or the several tools from RadarSoft) that will do the same thing, but will require some elbow grease to get wired together.
I find that it's the schema that causes most of the issues people have with querying a database. OLAP forces you to either a flat table or a Star/snowflake schema which is easy to query and comparably faster to the source oltp tables. So if you ETL your source to a flat table or star schema you should get 80% of what you get from OLAP, the 20% being MDX and analytic functions and performance.
Note that you should get a perf boost with a star schema in relational database as well and Oracle probably has analytic functions in PL/SQL anyways.
Try an open-source OLAP server called 'Mondrian'. IIRC the XMLA API on this is sufficiently compatible with AS to fool Pivot Table Services, which would allow you to use it with ProClarity or Excel.
IIRC it was originally designed to work over Oracle - it is a HOLAP architecture using base tables in the underlying relational store and caching aggregates. You can also make use of materialised views and query rewrite in the underlying Oracle database to do aggregates.
A few more thoughts on this topic:
Actually, Oracle Standard does have an OLAP facility based on a descendent of Express embedded in the database engine and storing its internal data structures in BLOBs in the main tablespaces. Using this is technically possible but not necessarily advisable for the following reasons:
It uses a highly non-standard OLAP query engine with very little third party tool support (AFAIK ArcPlan is the only third-party OLAP front-end supporting 10g+ OLAP), poor documentation for the query language and almost no third party literature describing it. This will work with B.I. Beans if you feel like writing a JSP front-end. It is not compatible with MDX at all. As of early 2006 the best Oracle could do when asked about drillthrough (this functionality was not supported in Discoverer 'Drake') was to recommend building a JSP apllication using B.I. Beans.
The reason that there is no migration path from Standard to Enterprise is that Enterprise is actually what used to be Siebel Analytics. Standard is the old Oracle OLAP/Express descendant which Oracle partners recommended avoiding even before Oracle bought out Seibel. Oracle has not even attempted to support migrating.
From this point of view, Mondrian is actually the most cost-effective OLAP solution for an Oracle Standard Edition shop. You can get a supported version from an outfit called Pentaho1. The next cheapest is Analysis Services, which comes with SQL Server. Following that you are into the likes of Hyperion Essbase, which will be an order of magnitude more expensive than SQL Server or any supported verion of Mondrian.
Whilst MS SQL Server offers OLAP, you'll need an Enterprise licence to use a cube in a live environment that is web-facing.
You might want as well to give a try to www.icCube.com - we're quite flexible on the data-source used to populate the cube and are quite cost effective compared to the big actors of the market.