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

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3
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2answers
275 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 ...
1
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2answers
57 views

Dimension for Product Properties based on Product Type - Sparse Dimension?

I am creating dimension of product properties for sales facts. Property of product depend of product type. For example: - Type = smartphone. Properties = model, OS, size - Type = book. Properties = ...
0
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2answers
39 views

How can I handle delayed records a month or older on a table clustered on time?

I have a two part question really for anyone working with data warehousing where they have large fact tables. Question 1 Lets say you have a table that has 500 million or more records in it that is ...
4
votes
1answer
327 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 ...
1
vote
1answer
33 views

DSV - SSAS Project - New 2 Columns In Table Change More then I Planned

I encountered a very weird thing. I added in my DWH table 2 new columns but when I refreshed the DSV after adding this to my multidimensional project I saw that more (3) columns have been "changed". ...
1
vote
1answer
37 views

Are there best practices or standardized syntax for writing transformation logic?

This may not be the appropriate forum, but its the closest I could find. I write a lot of source to target mappings for work. These documents just describe the operations/logic/transformations/etc. ...
1
vote
1answer
24 views

Table for actual values

I have a database where logging happens and is processed in a data-warehouse styled environment. This means there are staging cycles where the data comes in and then is processed. For a reporting ...
0
votes
1answer
91 views

Time out while connecting to the database. Current time out value is 30 seconds

I am installing a repository creation utility on a windows 8 x64 bit system and getting the following error: Time out while connecting to the database. Current time out value is 30 seconds When ...
0
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1answer
29 views

Dimensional Model for inheritance in dimensions

How are dimensions typically modeled in a dimensional model if one dimension logically inherits from another dimension? For example, assume I have an Employee dimension and a Driver dimension, where ...
5
votes
0answers
121 views

Why should I “Avoid partitioning dimension tables” on SQL Server?

SQL Cat have a list of tips titled Top 10 Best Practices for Building a Large Scale Relational Data Warehouse. Under section 4 - Design dimension tables appropriately they state: Avoid ...
2
votes
0answers
217 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 ...
2
votes
0answers
289 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) ...
2
votes
0answers
188 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 ...
1
vote
0answers
24 views

Which Azure Storage / Database Technology to make use of for large scale logging

I am looking into making use of Azure hosting services in order to develop a logging service for our company. Azure has a number of storage options available (I have listed links below). However I am ...
1
vote
0answers
71 views

ETL flow in Fact tables

I've got a simple theoretical question... If we discuss the principles, elements, design and implementation of a typical ETL flow for a dimension table then, in my understanding, (in short) I'd say ...
1
vote
0answers
18 views

Process dimension task is querying the wrong column!

I'm in the process of building a new data warehouse and I am starting out by building a few dimensions. I have created a fairly typical "Date" dimension and that seems ok. Now I am trying to create ...
1
vote
0answers
63 views

Best practices to segment people and attributes for advertising database

we have a database where we store people some attributes per person in the following tables: people (id, name, email, phone) people_attributes (id, person_id, attribute_name, attribute_value) ...
1
vote
0answers
79 views

how many fact tables do I need given I want to build an OLAP for Quotation Line Item and Purchase Order Line Item report?

My client wants a report that looks something like this on a daily basis. +---------------+-------------------------+-----------------+---------------------+-------------+ | ProductNumber | ...
1
vote
0answers
320 views

500GB Data Warehouse - how to split it into FileGroups?

OK, so I have: 500 GB DW 5 GB in smaller DBs 220 GB TempDB 350 GB in Log files. My machine is Fujitsu Primergy 64 cores (with HT) and 192 GB RAM. I have several IO locations: 540 GB in-server ...
1
vote
0answers
121 views

Should I use conventional or computed columns for trivial metrics in a fact table?

A fact table can often have measures which are basically trivial. For example Orders.NumOrders will probably be "1" for every real record (synthetic records representing "no order" may populate this ...
1
vote
0answers
51 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 ...
1
vote
0answers
780 views

An advice to design a fact table with a scd as a dimension

I have a problem of conception and I would like to get your ideas on how I'll be able to do what I am aiming. My goal is to create a datawarehouse, with three dimensions and one fact table so far. ...
0
votes
0answers
25 views

commonly used diagram for ETL

A the title indicates. Am i wondering what is the most commonly used diagram to explain an ETL process? In my case the process is rather linear, would a flowchart suffice? or is a Use-case also ...
0
votes
0answers
24 views

Which Azure service for use as data warehouse/analysis store?

We currently have a database running in SQL Server 2012 Standard. We need to export data periodically (a "data dump") of a particular set of data to "a location to be decided" where the client's ...
0
votes
0answers
17 views

Database choice for structured big data to be queried with SQL

I have a system that harvests and registers a total of 500K (master table) and 100 million (detail table) into a two table master/detail database, per day. The detail table has around 50 fields, two ...
0
votes
0answers
26 views

Fact Table with day grain that has many records that don't change

So I have a daily snapshot fact table that stores financial account balances. Normally, this would be pretty easy, just have a record for every day for every account. My problem is that table would ...
0
votes
0answers
9 views

Pentaho getfilename error

I am try to send 20 mail with attachments using pentahi DI, Jobs are like below Get File Names--->Add constants--->Mail But some mails are not send with below error, Thay say files are not ...
0
votes
0answers
37 views

SSAS bridge table with Slowly changing dimensions

I am designing a datamart using the basic principles of Kimball for use in SSAS. I have a many many to many attribute relationships (multi-valued dimension objects), however I have a few questions: ...
0
votes
0answers
38 views

What options exist for replicating SQL Server over the public internet

Specifically, I'd like to set up a reporting copy of a SQL Server 2012 transactional database. This primary runs in a managed services provider, and I want a copy in an AWS EC2 SQL Server instance. ...
0
votes
0answers
56 views

Proxy for MDW data collection on remote servers - SQL Server 2012

I am trying to setup data collection (for disk usage) from remote servers and upload it to my MDW database. I understand I will need a proxy set up for the agent to do this but which subsystem to I ...
0
votes
0answers
23 views

Data Warehouse for reporting - 6 Dimension tables,or 1 table and 6 views?

Problem: I have been asked to add a Dimension table to our data warehouse and create the ETL tasks to populate it. Lets call the table "DimInternalFault". The source table for DimInternalFault is ...
0
votes
0answers
12 views

Datavaulting polymorphic association (conditional) columns

I'm trying to implement data vault into our business but I'm stuck with the data vault model. We are having some source tables (3NF) which contain some polymorphic association (conditional) columns: ...
0
votes
0answers
113 views

Handle Duplicate entries in Fact table in Data Cube

We have been constructing data cube for our project in which we are facing a problem like 1 to many relationship in the dimension tables and making entries in fact table (duplication). ...
0
votes
0answers
53 views

Is there a way to check which views have data? Oracle 11g

I'm undergoing a cleanup process for a data mart design. However, I want to get rid of any views (in the design) which result in having 1 or less rows of data. Instead of manually going through ...
0
votes
0answers
117 views

Is there value in storing audit fields in a fact table?

I've always stored at least two basic housekeeping fields in all of my dimension and fact tables: DateCreated and DateModified. However, this adds two fairly wide (eight bytes each, in MS SQL) ...
0
votes
0answers
166 views

Data warehousing: data transfer process too slow with larger batches

I have two primary instances of SQL Server, one for OLTP and one for reporting. The data warehouse for reporting is basically a Type 2 SCD: every table has DWDateStart and DWDateEnd columns and the ...
0
votes
0answers
60 views

Physical Table being used a Temp Table in a warehosue. Any advantage?

As I stated in previous posts I've inherited a warehouse based on SQL Server framework. In my continuous review of existing components and the practices adopted by the predecessors I found something ...
0
votes
0answers
39 views

Accounting - Dimention table in mysql

I am designing a accounting and mini erp system. I use a date dimension table to track all date related data. In oracle we can have many schema for a database. so we could create each schema for ...
0
votes
0answers
98 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 ...
0
votes
0answers
187 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 = ...