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5
votes
2answers
456 views

Alternative to EAV for dynamic fields in a star schema data warehouse

I need to support dynamic fields and values in a big datawarehouse for storing API requests log, my user case is that I need to store all API requests query string and able to perform query against ...
5
votes
2answers
850 views

Cardinality rule for bitmap indexes

The Oracle documentation includes the following advice: A bitmap index should be built on each of the foreign key columns of the fact table or tables In that reference, there is even a bitmap ...
5
votes
1answer
604 views

Schema for analytics table in Postgres

We use Postgres for analytics (star schema). Every few seconds we get reports on ~500 metrics types. The simplest schema would be: timestamp metric_type value 78930890 FOO ...
4
votes
2answers
326 views

Open source and commercial tools to build dynamic queries of fact tables in star schema

What user interfaces or tools (commercial and/or open source) can query a star schema model (Ralph Kimball dimensional model)? So for example, if we have X fact tables, and Y dimension tables, and Z ...
4
votes
1answer
234 views

How to handle “many columns” in OLAP RDBMS

I have a fact that has around 1K different numerical attributes (i.e. columns). I would like to store this in to a column-oriented DB and perform cube analysis on it. I tried to design a star ...
3
votes
1answer
223 views

Should I snowflake or duplicate it across my facts?

I'm building up a data warehouse to be used by SSAS to create cubes on, and I'm debating between two possible schemas. In my warehouse, I've got two different fact tables that tracking daily changes ...
2
votes
1answer
272 views

IP Address lookup star schema design

I am working on a project in which we need to do IP Address lookups. So for this we have got the datasets and now the next steps is to populate this datasets in to the table. And then have some ...
1
vote
1answer
420 views

~2 Billion row fact table in star schema on Oracle. Advisable? [closed]

Let me start with: I am not a DBA; I am a backend developer. It has been suggested that, for a report schema, I implement a star schema where-in the fact table can have ~2B rows before being ...
1
vote
2answers
456 views

Data warehouse support tickets

I'm starting to design a data warehouse for a company. The first questions we're trying to resolve are regarding their support ticketing system. My initial schema is as follows Now one of the ...
1
vote
1answer
116 views

Best approach for populating date dimension table

I am looking to populate a date dimension table in a SQL Server 2008 database. The fields in the table are as follows: [DateId] INT IDENTITY(1,1) PRIMARY KEY [DateTime] ...
0
votes
1answer
38 views

How do I choose primary keys for star schema BI data warehouse?

I am extracting sales turnover data from a Microsoft Dynamics Database into another SQL database that will be used by the BI tool of choice. This data is coming from G/L (general ledger) entry items. ...
0
votes
1answer
90 views

date dimension OLAP cube design

I have a sales reporting system with incoming data like this date,editionID,outletId,Measure1,Measure2 2013-01-01,2,532,11,24 etc... I am new to designing data cubes (for the pentaho BI suite) and ...
0
votes
0answers
25 views

Shared measures in fact tables

I'm working on a star-schema and trying to find a best practise for the database design. I have three (at this moment) dimension tables for several facts. Most of the facts look-a-like (meaning ...
0
votes
0answers
8 views

Managing schema migrations in Mondrian

Managing schema changes across dev, stg, prd is something we do well in our home-grown solution today. Specifically, at least one downstream team consumes our star schema. They're considering ...
0
votes
0answers
19 views

Many people, one event, multiple factors - OLAP

Have a modeling problem here... first the back-story... We deal with accident data on our project, 1 vehicle-crash can have multiple people and vehicles involved, and many associated factors across ...