I found a lot of material on the various tools, and quickly became competent in their use. I also quickly got up to speed on star schema versus snow flake schema, and the divvying up of data into facts and dimensions. The thing that always puzzled me was, how do you decide what goes...
The data in the retailer's data warehouse system has two important components:dimensions andfacts. The dimensions are products, customers, promotions, channels, and time. One approach for identifying your dimensions is to review your reference tables, such as a product table that contains everything...
The data in the retailer's data warehouse system has two important components: dimensions and facts. The dimensions are products, customers, promotions, channels, and time. One approach for identifying your dimensions is to review your reference tables, such as a product table that contains eve...
DISCOVERY OF FACTSFILE SYSTEMMultidimensional Data-warehousing applications play prominent role in facilitating business intelligence, and subsequent strategic decision making for the industry. It provides a good starting point for data-mining applications, which cater to different segments of industry, ...
If I have two facts that make use of the same dimension 'product', would I have one dimension 'product' or one dimension per fact table so that I can maintain them separately? I can see how this can be a pain in ETL to have to deal with another dimension but at the same time, ...
what you don't want to do is have your previous snapshots updated to point to latest member as facts they are immutable and they should always point to the record as of the snapshot period Share Improve this answer Follow answered Feb 15, 2018 at 8:19 Jason Horner 11311 silv...
This new surrogate key is how the dimension is joined to the sales facts made for that version of the sales person as you can see belowFor those of you in black and white, Steve's sales in E region are in orange and those when he moved to SW region are in blue. We can sum a...
SCD2 is a dimension that stores and manages current and historical data over time in a data warehouse. The purpose of an SCD2 is to preserve the history of changes. If a customer changes their address, for example, or any other attribute, an SCD2 allows analysts...
Surrogate identifiers enable you to hook facts to any dimension level as opposed to the lowest dimension level only. You must use a surrogate key if: your dimension is a Type 2 slowly changing dimension (SCD). In these cases, you can have multiple dimension records loaded for each Natural ...
When a record is updated in a dimension table, the context for existing facts is restated. This effect can give rise to confusion. Usage: About 50% of the time. When to use Type 1: Type 1 slowly changing dimension should be used when it is not necessary for the data warehouse to keep...