What Is Data Warehouse Design?

Hey, are you here to find a solution for a consolidated and easy-to-access “home” for your business information, which is usually transferred from different places, often unrelated to each other? Then, you probably need to think about creating a digital space where it will be integrated, cleaned, structured, and stored accordingly, for further use in your regular business operations. But what is this space? Let’s find it out right now.

What Is Data Warehousing?

In a nutshell, it is a repository where your business data comes from disparate sources, where it is brought to the proper quality, and where it is stored, providing individuals with the appropriate rights with easy and fast access to it. Typically, such repositories serve as one of the central components in automated analytical solutions, but, as practice shows, the range of their application can be much wider.

Key Components of a Data Warehouse

In general, its main components are considered to be the following:

• Sources, from which structured and unstructured information comes – these can be third-party databases, tables, systems, applications, etc.;
• Data Extraction, Transformation, and Loading (ETL) tools, which define scenarios for extracting, transforming, and loading the information;
• Data warehouse database, which is the main repository (usually in the form of a database management system, DBMS) with already prepared, i.e., cleaned and structured data, that can be used for analytics, reporting, and other business tasks without additional manipulation;
• Metadata repository, which includes the permissible data types and the rules according to which this data will be used;
• Query and reporting tools, which define algorithms for fast and unified access to data, as well as its analysis;
• Data mart, a subset of the data warehouse that is used for individual business tasks (this can imply, for example, marketing data warehouse design) which formation occurs either directly through the collection from disparate sources or pre-preparing within a consolidated space.

Core Principles of Data Warehouse Design

Now, let's talk about the main data warehouse design principles:

• A clear definition of business requirements and goals, as well as metrics that allow you to objectively assess the degree of their achievement;
• Understanding how information is integrated from multiple sources and what should be the unified format after its transformation;
• Choosing the right type of data modeling – these can be star schemas, snowflake schemas, fact tables, and so on;
• Choosing the right methods and data warehouse software to ensure the quality and consistency of information, in particular, the methods of cleansing, validation, and supplementing of data;
• Planning, scaling, and managing the performance through various methods of indexing, partitioning, compression, etc.;
• Choosing the right tools for metadata management to simplify and improve access to the information;
• Ensuring security and access based on policies and rules (usually, this is achieved through the implementation of advanced encryption algorithms, the introduction of access policies for different user groups, as well as providing reliable authentication and authorization methods);
• Implementing end-to-end monitoring for ensuring data quality and security, performance of processes occurring within the data warehouse, and so on.

Steps in Data Warehouse Design

In this section, we invite you to consider the key steps leading to a successful and agile data warehouse design.

Requirement Gathering

According to the principles to design a data warehouse we defined above, the key to effective data warehouse design is to gather business requirements and clear business goals that it should fulfill. It is also important to identify the requirements for security, scalability, and performance of the repository.

Data Modeling

This is not yet a practical stage, but it still requires the participation of specialists – in particular, it implies the identification of entities, their attributes, as well as possible relationships between them. After this, the most suitable type of DBMS implementation needs to be selected – for example, in the form of tables, columns, indexing, etc. After this, you have to make sure that the selected type performs all the tasks assigned to it according to the predetermined requirements.

ETL Process Design

We have already explained above what the ETL process means, and this stage actually involves choosing the right tools and scenarios for their use.

In particular, you will need to define methods for extracting information from disparate sources (these can be database queries, API calls, file transfers, etc.), methods for bringing data to a single format and ensuring its proper quality (since you will most likely have to deal with big data, there may be many inconsistencies), methods for aggregating data to create complex information structures, automation methods for bulk loading of data (this can be full or incremental loading, and so on) with the usage of temporary storage areas, methods for detecting and eliminating data errors, as well as methods for checking data for completeness and accuracy.

Database Schema Design

There are several well-known data warehouse design patterns, such as:

• Star, which has a fact table at its center and dimension tables associated with it around it;
• Snowflake, which is a more complex Star and also implies additional dimension tables that surround each base dimension table;
• Galaxy, which contains two fact tables and the dimension tables between them.

Data Integration

Now, you can start integrating the data using the previously defined ETL tools and technologies. At this step, you need to make sure that everything works as intended, and the data is transformed into the required unified format.

Data Storage Solutions

At this stage, you need to choose specific data storage solutions according to your requirements for the expected data volume, performance, scalability, and cost. Usually, the choice is made between relational databases, columnar databases, data lakes, and cloud data warehouse solutions.

Data Presentation Layer

Finally, to design data warehouse, you will need to understand what your data presentation layer will be – the layer at which end users will be able to seamlessly access the data and use it to solve specific business problems. This includes developing interfaces, dashboards, reports, and various data visualization tools.

Conclusion

Now that you have a clear guide to data warehouse design, you can begin implementing it with a full understanding of the principles and stages on which it is based. If you would like to delegate this comprehensive task to seasoned data warehouse development specialists, just contact us.