“Big Data”, “Data Lake”, “Data Swamp”, “Hybrid Architecture”, “NoSQL”, “Hadoop” … terms you are confronted with very often these days when you are dealing with data. Furthermore, the question comes up if you really need a data warehouse nowadays when you deal with a high variety and volume of data. We want to talk about what a data lake is, if we need a data warehouse when using NoSQL platforms like Hadoop, and how it is combined with Data Vault.
WHAT IS A DATA LAKE?
Last month we talked about a hybrid architecture in Data Vault 2.0, where we explain how to combine structured and unstructured data with a hybrid architecture. To follow up on this topic, we now want to explain how your business users (especially power users) can take a benefit from it with the managed Self-Service Business Intelligence (mSSBI) approach in Data Vault 2.0.
ABOUT SELF-SERVICE BI
Self-service BI allows end-users to completely circumvent IT due to this unresponsiveness of IT. In this approach, business users are left on their own with the whole process of sourcing the data from operational systems, integration and consolidation of the raw data. There are many problems with this self-service approach without the involvement of IT:
Business users expect from their data warehouse systems to load and prepare more and more data, regarding the variety, volume, and velocity of data. Also, the workload that is put on typical data warehouse environments is increasing more and more, especially if the initial version of the warehouse has become a success with its first users. Therefore, scalability has multiple dimensions. Last month we talked about Satellites, which play an important role regarding the scalability. Now we explain how to combine structured and unstructured data with a hybrid architecture.
LOGICAL DATA VAULT 2.0 ARCHITECTURE
The Data Vault 2.0 architecture is based on three layers: the staging area which collects the raw data from the source systems, the enterprise data warehouse layer, modeled as a Data Vault 2.0 model, and the information delivery layer with information marts as star schemas and other structures. The architecture supports both batch loading of source systems and real-time loading from the enterprise service bus (ESB) or any other service-oriented architecture (SOA).
Data Vault 2.0 is a concept for data warehousing, invented by Dan Linstedt. It brings many new features that help anyone who is concerned with Business Intelligence entering a new age of data warehousing. Data Vault 2.0 is a Big Data concept that integrates relational data warehousing with unstructured data warehousing in real-time. It is an extensible data model where new data sources are easy to add. When our founders wrote the book, they required a visual approach to model the concepts of Data Vault in the book. For this purpose, they developed the graphical modeling language, which focuses on the logical aspects of Data Vault. The Microsoft Visio stencils and a detailed white paper are available on www.visualdatavault.com as a free download.
SATELLITES IN VISUAL DATA VAULT
Satellites add descriptive data to hubs and links. Descriptive data is stored in attributes that are added to the satellite. The individual attributes are added to the satellite one at a time. A satellite might be attached to any hub or link. However, it is only possible to attach the satellite to one parent. Read More
With the advent of Data Vault 2.0, which adds architecture and process definitions to the Data Vault 1.0 standard, Dan Linstedt standardized the Data Vault symbols used in modeling. Based on these standardized symbols, the Visual Data Vault (VDV) modeling language was developed, which can be used by EDW architects to build Data Vault models. When our founders wrote the book, they, required a visual approach to model the concepts of Data Vault in the book. For this purpose, they developed the graphical modeling language, which focuses on the logical aspects of Data Vault. The Microsoft Visio stencils and a detailed white paper are available on www.visualdatavault.com as a free download.
LINKS IN VISUAL DATA VAULT
In June this year we published another newsletter how hubs are modeled in the accounting industry. In this Newsletter we explain the function of standard links and how the modeling in the banking industry works.
Links connect individual hubs in a Data Vault model and represent either transactions or relationships between business objects. Business objects are connected in business. No business object is entirely separate from other business objects. Instead, they are connected to each other through the operational business processes that use business objects in the execution of their tasks. The image below shows a link that connects two hubs (a standard link has to have at least two connections). Read More
One common requirement in data warehouse projects is to provide data lineage from end-to-end. However, custom solutions (for example custom Meta Marts for self-developed Data Vault generators) or tools from different vendors often break such end-to-end data lineage.
Unlike business or technical metadata, which is provided by the business or source applications, process execution metadata is generated by the data warehouse team and provides insights into the ETL processing for maintenance. The data is used by the data warehouse team or by end-users to better understand the data warehouse performance and results presented in the information marts. One type of process execution metadata is the control flow metadata which executes one or more data flows among other tasks. Logging the process execution provides a valuable tool for maintaining or debugging the ETL processes of the data warehouse because it provided information about the data lineage of all elements of the data warehouse. Read More