A database system optimised for reporting, particularly in aggregate. Often, but not always implemented using a star schema.

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29 views

Dimension or Degenerate Dimension?

I am taking a course on data warehousing. Currently, I am reading through Ralph Kimball's Data Warehouse Toolkit. I understand that a degenerate dimension is a dimension key that is stored in a fact ...
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2answers
114 views

Daily snapshot fact table

I have a list of products per costumer. Costumers can delete or add products to their list. I want to know in each day what is the list of products (and count) by costumer. My first approach is to ...
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1answer
211 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 ...
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1answer
42 views

Migrate Management Data Warehouse to a New Instance

Is there a defined procedure to follow for moving a SQL Server 2012 management data warehouse to a new server\instance? We intend to setup an MDW on a test sql server instance first, but will then ...
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1answer
283 views

creating a report on the mysql jasperReport server

I have mysql local database, in it I have sample data mart. I have installed jasperReport server to my computer. Just using this tool, I want connect to the local mysql database and just create a pdf ...
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1answer
18 views

Constellation Schema; Relationships between fact tables

What are acceptable types of depedendcies between facts in a multiple-fact schema? Conceptually talking, As you know a Multi-Dimensional Model may have multiple facts (like in a constellation ...
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1answer
24 views

How to design and implement a datawarehouse using oracle data integrator 12c?

I want to design and implement a datawarehouse using oracle products. The most recently documented product to do that is Oracle Warehouse Builder 11g R2. But when installing, oracle database 12c, OWB ...
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0answers
127 views

Updating a big replicated Dimension (SQL Server PDW)

We use a SQL Server PDW appliance for our data warehouse. One of the tables in our warehouse is a replicated table with about 20 million rows. As part of our ETL process we need to expire old records ...
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139 views

Geographic Hierarchies in a OLAP Cube / Data Warehouse

Are the following geographic hierarchies correct? Do any US/Canadian area codes cross state/province lines? Do any US/Canadian counties cross state/province lines? Are there countries with counties ...
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114 views

How to gracefully handle a source database restore from backup in a data warehouse

We are facing a challenging situation with our data warehouse source databases. Frequently these sources databases will be restored from backups. There is a high turnover of data entry persons who ...
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62 views

What type of fact table / loading solution for a reservation system?

I am designing a Data Warehouse with SQL Server 2012 and SSIS. The source system handles hotel reservations. The reservations are split between two tables, header and header line item. The ...
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0answers
31 views

Monoblock, Multiblock queries?

What exactly mean the terms monoblock / multiblock queries in data warehouses when talking about materialized views? Does a monoblock query just use one data source (a normal table) while a multiblock ...
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11 views

Does data guard support Oracle Warehouse Builder?

Does data guard support Oracle Warehouse Builder (both 11.2.0.4)? If not, what is the procedure to setup/configure my OWB project (repository, workspace, control center service...) on the standby ...
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10 views

When there is a Type 1 and type 2 SCD in a dimension table, how are updates to the type 1 column handled after the type 2 column is updated?

Eg: ID Type1SCD Type2SCD FromDate todate 1000 100 ABC 01-JUL-2014 NULL Now, Type2SCD is updated ID Type1SCD Type2SCD FromDate todate 1000 100 ABC 01-JUL-2014 12-JUL-2014 ...
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69 views

Is there better way to design SQL tables

I need to design a quick application for small warehouse. I just want to check if there is a better design approach. I am using polymorphic associations for comments tables. Business Rules If ...
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0answers
40 views

Running materialized view refresh in parallel

I have a large materialized view that is refreshed periodically (complete refresh) and I would like to do it in parallel. I can already run the query part in parallel but the problem is (much slower) ...
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0answers
71 views

MySQL: Error 1118 using create table select and barracuda file format

We want to create the equivalent of some materialized views in a read-only slave for really performant reporting. The queries used to generate these tables span 19 tables with a fair number of ...
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80 views

How much RAM do I need?

Let's assume a query like the following as typical: select A.`date` as `date`, count(*) as N from A as A join B as B on B.id = A.b_id join C as C on C.id = B.c_id join D as D on D.id = ...