olap

问题 What is the recommended pattern for managing Mondrian database connections? I am using Mondrian as a library in a Scala/Play Framework web application. For example: var connection try { connection = DriverManager.getConnection(connection_string).unwrap(classOf[OlapConnection]) val result = connection.createStatement.executeOlapQuery(mdx) // ... use the result ... } finally { if (connection) connection.close } Is calling close in a finally block the right approach? How do I configure a

问题 I denormalising a OLTP database for use in a DWH. At the moment I am denormalising studygroups. Each studygroup has a key pointing towards 1 project. Each project has a key pointing towards 1 department. Each department has a key pointing towards 1 university. Each universityhas a key pointing to 1 city. Now I know that you are supposed to denormalize the sh*t out your OLTP but in this dwh department will be a dimension on its own. This goes for university also. Would it suffise to add a key

问题 I'm wondering if there is any desktop OLAP solution that can use SQL Express (and therefore does not require Analysis Services) I've been tasked with finding a way to allow our customers to do 'Ad-Hoc' reports, but the vast majority of them are on Sql Express, In previous jobs, customers have had Analysis Services and typically Cognos or Crystal Reports, so all that was required was to design the cube. 回答1: SQL Express is pretty limited, I don't know of any OLAP capabilities. Although, we use

问题 Is it possbile to restrict a Role in Dimension Data by allowing him to see only siblings in the parent-child Hierarchy? Example Hierarchy: EMEA 100 UK 50 London 30 Southampton 20 France 50 Paris 10 Lyon 40 To see only: EMEA 100 UK 50 France 50 回答1: I've received the expected result with the following MDX statement NONEMPTY( descendants( [Dim Branch Hierarchies].[Branch Hierarchy] ,,leaves ) , ( [Measures].[GrantedHi] ,StrtoMember( "([Dim Users].[Account Name].[Account Name].["+ Username()+ "]

问题 Is it possbile to restrict a Role in Dimension Data by allowing him to see only siblings in the parent-child Hierarchy? Example Hierarchy: EMEA 100 UK 50 London 30 Southampton 20 France 50 Paris 10 Lyon 40 To see only: EMEA 100 UK 50 France 50 回答1: I've received the expected result with the following MDX statement NONEMPTY( descendants( [Dim Branch Hierarchies].[Branch Hierarchy] ,,leaves ) , ( [Measures].[GrantedHi] ,StrtoMember( "([Dim Users].[Account Name].[Account Name].["+ Username()+ "]

问题 I've been playing with a script of Chris Webb's found here: http://cwebbbi.wordpress.com/2007/06/25/advanced-ranking-and-dynamically-generated-named-sets-in-mdx/ The adapted script is this: WITH SET MyMonths AS TopPercent ( [Date].[Calendar].[Month].MEMBERS ,20 ,[Measures].[Reseller Sales Amount] ) SET MyEmployees AS [Employee].[Employee].[Employee].MEMBERS SET MyMonthsWithEmployeesSets AS Generate ( MyMonths ,Union ( {[Date].[Calendar].CurrentMember} ,StrToSet (" Intersect({}, {TopCount

问题 What makes access to OLAP Cubes/Datamarts and similar datastructures, faster than to relational databases? EDIT A bounty of 200 will be provided asap. 回答1: I would say mainly because of different purposes. OLAP cubes / datamarts are used mainly in read mode for data analysis by business users whereas I'm assuming when mentioning relational DBs you're talking about OLTP usage requiring for example ACID transactions. Those different purposes means: different constraints for the implementation

问题 I have a fairly standard OLTP normalised database and I have realised that I need to do some complex queries, averages, standard deviations across different dimensions in the data. So I have turned to SSAS and the creation of OLAP cubes. However to create the cubes I believe my data source structure needs to be in a 'star' or 'snowflake' configuration (which I don't think it is right now). Is the normal procedure to use SSIS to do some sort of ETL process on my primary OLTP DB into another

问题 I wish to change the default aggregation from SUM to SUM on Distinct ID Values. This is the current behaviour ID Amount 1 $10 1 $10 2 $20 3 $30 3 $30 Sum Total = $90 By default, I am getting a sum of $90. I wish to do the sum on distinct ids and get a value of $60. How would I modify the default Aggregation Behavior to achieve this result? 回答1: Design your data as a many-to-many relationship: create one table/view having one record per ID and the amount column from the data shown in your

问题 I wish to change the default aggregation from SUM to SUM on Distinct ID Values. This is the current behaviour ID Amount 1 $10 1 $10 2 $20 3 $30 3 $30 Sum Total = $90 By default, I am getting a sum of $90. I wish to do the sum on distinct ids and get a value of $60. How would I modify the default Aggregation Behavior to achieve this result? 回答1: Design your data as a many-to-many relationship: create one table/view having one record per ID and the amount column from the data shown in your