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

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5 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: ...
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0answers
18 views

Informatica vs datastage? Wich is better for a beginner? [on hold]

first of all sorry for my english. Im a web developer, i want to change my career ,i want to be an etl developer. I have a good understanding of database and i have been using mssql for the past year, ...
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1answer
8 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 ...
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1answer
22 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. ...
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0answers
19 views

Best way to perform real time analytics on a growing collection of json file ( very large ) [closed]

I have a very large collection of JSON file (tens of millions) on S3 and I need to have some kind of aggregation (perform continuously as the collection grows). The aggregation is mainly counter ...
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0answers
60 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). ...
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1answer
62 views

Update Cube data

We are using OLAP in our Project. We are facing a scenario where we need to update the cube with real time data on daily basis. I need some suggestions about an optimal way for updating the data in ...
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0answers
22 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 ...
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1answer
83 views

Server roles in SQL Server 2016

There are 3 new server roles in SQL Server 2016: mediumrc largerc xlargerc Any idea what these are for? Google doesn't give any information about these.
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11 views

How to set missing colunms as a null in datastage 9.x.x

I have a sequential file with difference length fields, I want to set missing fields value as a null when I import using datastage, (Not mean set empty fields as a null)
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0answers
13 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 ...
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0answers
49 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 ...
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1answer
26 views

How to load .dat files to oracle database

I have .DAT files extracted from telecom switch. I want to upload this file to an Oracle server using IBM data-stage ETL tool. Unfortunately these files are not readable format. This is a picture ...
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2answers
58 views

Do valid to/from columns on a fact table make sense?

I recently came across "valid from" and "valid to" columns on a fact table. Obviously this is common for dimensions but I've not seen them on fact tables before and can't find any info suggesting ...
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1answer
17 views

New fact table or new dimension

I have a fact table with 2 dimensions: cohort_id date_id Each record contains the amount of active users from a specific cohort at a particular date - typical structure for the cohort analysis. ...
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0answers
39 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) ...
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1answer
47 views

How to keep the data warehouse synchronised with the source systems? [closed]

I'm a DBA who is responsible for exporting data from an ERP system for Business Intelligence purposes. The data from ERP system is being sent to the data warehouse and they are used in the ETL ...
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1answer
60 views

Name for intermediate aggregated data [closed]

We have raw data and aggregated data as well as sometimes multiple levels of aggregation between. Is there a name for the data in that intermediate "state" of aggregation? Just like how we have Real ...
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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 ...
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0answers
44 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) ...
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2answers
149 views

How to prevent users other than DBAs from creating database links

To begin, please keep in mind that I am a very green DBA. I have done prior research and have not really found anything too promising, or maybe it just seems that way because I am still struggling in ...
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1answer
27 views

Data warehouse: Can I tell any details from Source System on delays or blocks? [closed]

I have a MS SQL Server 2012 machine that is acting as our data warehouse currently. We are having issues with long running jobs, and am curious if there is a way to get detailed historical logging on ...
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0answers
69 views

Use trigger to update SCD2 End date and IsCurrentRow flag

I'm implementing a data warehouse that has type 2 slowly changing dimensions. When a change is made to a SCD type 2 column, I need to insert a new row into the dimension for that entity and also ...
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0answers
51 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 | ...
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1answer
90 views

What to do when facts change frequently in a star schema for data warehouse?

I have a Quotation Management system that I built as a CRUD web app. Over time, I realized I need to improve it so that management can have their reports. Hence I studied the Kimball method of data ...
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1answer
103 views

How to change a web application that now needs to become OLTP and OLAP application?

Previously, I did a simple web application for an enterprise client using PHP and MySQL. After some time, it has grown to a point where I realized after talking with people here that I need to treat ...
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2answers
187 views

Have a separate database for data warehousing?

I have built a typical web application using PHP and MySQL for enterprise usage. The MySQL database is 3NF as much as possible. However, as time goes by, the requests for the data appear to be more ...
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0answers
80 views

Fact table linked to Slowly Changing Dimension

I'm struggling to understand the best way to model a particular scenario for a data warehouse. I have a Person dimension, and a Tenancy dimension. A person could be on 0, 1 or (rarely) multiple ...
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4answers
2k views

Datawarehouse bad practice?

In our Datawarehouse context, we have to update some record in fact tables inside our ETL. One thing we did is to create nonclustered indexes just before the heaviest queries, and drop them ...
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1answer
74 views

How to migrate data of to another sql server

Good day, I have a database running on a virtual machine hosted at our ISP. It is a fairly large database which has about 5GB of data inserted into it every day (network logs). It is partitioned ...
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22 views

What known strategies, if any, can I use to validate a Slowly Changing Dimension?

I have a customer dimension in our data warehouse (SSAS 2014 Multidimensional). It is set up as a Type II SCD, with just Start and End Date fields to track changes. (null end date = current). As our ...
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3answers
66 views

Data Warehouse measures without a corresponding dimension

I have an operations database that contains this table: salesQuality salesPrice salesCategory According to my business requirements, the salesQality and salesPrice are measures. However, ...
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1answer
98 views

Best way to document Dwh views [closed]

I works in a company that provide Dwh views as an API for external Customers (We use MS-SQL 2008 & 2012). every once in a while we release new views and updates the existing views. We have ...
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0answers
88 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 ...
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49 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 ...
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35 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 ...
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2answers
91 views

Is it good or bad practice to have a fact table relate to the same dimension table multiple times?

I'm new to DW/BI, and this seems like a pretty basic question, but I can't seem to find a good answer. I have a fact table that would have more than one date associated with it, so I was thinking ...
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0answers
63 views

Required Information to start oracle warehouse builder

I am using windows 8 64 bit . I want to install Oracle Warehouse Builder on my system. I have installed Oracle 11g and come to know that Warehouse Builder is already a part of it. But when I start ...
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2answers
287 views

TSQL vs SSIS Lookup

I was trying to find some well performing Tsql equivalents for the SSIS Lookup component. Especially for Fact table loading. After few different query patterns the most obv performed the best: ...
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0answers
142 views

How alter on infobright (BRIGHTHOUSE storage engine) actually works

I have been using infobright-3.4.1 (5.1.40) for data warehousing. I know it is outdated version but there no plan to upgrade the version currently. Even though infobright is build on mysql, the way it ...
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3answers
823 views

Purpose of Data Warehousing?

I have been reading up on Data Warehousing and its purpose. The main purpose seems to be to track historical data and whatever changes may have occurred over time. The DW book I am reading gives a ...
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1answer
18 views

Conformed Fields or Snowflake? - Shop and Customer Location

I have shop dimension and customer dimension which both has location information. Should I create location dimension to correlate shop location and customer location? I believe this one is called ...
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1answer
43 views

MySQL data to Postgres every X time

Our team (Uni students) have a project that we are updating. Old project team has a Live MySQL database. We want to make a archive/warehouse from it in PostgreSQL. My question is: How can we import ...
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2answers
43 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 = ...
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232 views

Calculate sum of a whole column in IBM Datastage without any grouping

I have a table in oracle with salary as one of the columns. I want to calculate the sum of this salary column. It is pretty simple in SQL sum(salary) but I have made some dimensions and facts using ...
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131 views

Problem in Incorporating filters into Data Warehouse design

While implementing a data warehouse (proof of concept) I have a requirement to incorporate a user level save-able filter on dimensions. The requirement is a proof of concept so I have the liberty to ...
2
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0answers
120 views

SQL Server, Mount Points and File Groups design [closed]

I am looking for some advice on a data warehouse we are building. Specifically around SQL Server, mount points and file groups. We have two design options for how mount points and files groups should ...
13
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2answers
917 views

Clustered columnstore indexes and foreign keys

I am performance tuning a data warehouse using indexes. I am fairly new to SQL Server 2014.Microsoft describes the following: "We view the clustered columnstore index as the standard for storing ...
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1answer
39 views

Separating system databases from MDW SQL Server 2008 R2

We have the Management Datawarehouse feature configure on two of our SQL Servers. Both point to the same central database and upload their results to it. Everything works fine with the built in ...
2
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1answer
39 views

Modeling Conversion Events in a Data Warehouse

How should I model conversion events? For instance, if a sales opportunity goes from "stage: prospecting" to "stage: validating", should that be treated as a changing dimension, or a conversion event ...