How to Perform Data Dictionary Mapping for Seamless Data Integration

How to Perform Data Dictionary Mapping for Seamless Data Integration

May 2025 | Source: News-Medical

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Organizations in today’s data-driven environment can be working with data sources from various outdated systems, cloud systems, or even from the third-party application; and with that, data integration is happening continuously. One important step in leveraging successful integration is ensuring that data dictionary mapping is taking place. Data dictionary mapping is the alignment of elements of data from multiple collecting and receiving systems to ensure the data will be consistent, accurate, and flowing through various platform types.

In this article, we will discuss what data dictionary mapping is, why it’s important, and how to execute proper data dictionary mapping to accomplish seamless data integration.

What is Data Dictionary Mapping?

Data dictionary mapping is the process of matching fields or data elements from the data dictionary of one system to the data dictionary of another system. A data dictionary is essentially a catalog or repository of metadata that defines and describes data elements (the metadata includes the data element’s name, type, length, allowed values, and relationship to other data). [1]

For example, a system might store a customer’s birthdate as DOB, while another system might use Birth_Date. Correctly mapping the data elements ensures that when integrated, or when migrated data between systems, the data is understood and interpreted by the systems in a consistent manner.

Key Features

The Importance of Data Dictionary Mapping

Inconsistent and/or erroneous data mapping can lead to incorrect data transformation, loss of data or other misinterpretations having high risk operational and compliance implications. [2]

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The Benefits of Data Dictionary Mapping

  • Correct Data Integration: The data being transmitted between systems is accurate.
  • Data Consistency: Data integrity remains intact across disparate platforms.
  • Interoperability: Interoperability is improved between disparate systems.[3]
  • Compliance/Governance: Helps meet compliance regulations since all data definitions will be standardized.
  • Onboarding and Migration: Reduces time on upgrades, mergers, or transitions of vendors.
Benefits of using a data dictionary

1. Determine Scope and Objectives

Before you get going, you will want to be clear on the goals of the data dictionary mapping exercise:

What systems are being integrated? What data domain (for example, customer, finance, HR) is in scope? Are you migrating, synchronizing, or standardizing data? Knowing the ultimate purpose of the project will help you design your data dictionary mapping service around explicit business requirements.

2. Gather the Data Dictionaries from all Source Systems

Every source system that you are integrating should have a published data dictionary. In the event there is no data dictionary for the source, you will need to either build one through data profiling or ask the system administrator to help you. [4]

What you will want to get:

  • Field names
  • Data types
  • Lengths
  • Constraints (for example, nullability, unique keys)
  • Relationships and dependencies

3. Normalize and Clean Metadata

Before you can start to map, proper preparation requires that you normalize and clean your metadata. This normalization and cleaning may entail many different actions, such as:

  • Identifying and eliminating duplicate records
  • Harmonizing your naming convention and terminology
  • Eliminating any deprecated/obsolete fields
  • Replicating synonyms and abbreviations (Cust ID or Customer Identifier)
  • This is imperative to reduce ambiguity in your mapping process.

4. Identify Mapping Relationships

This is the meat of the data dictionary mapping exercise. Determine how fields relate to each other, and there are common types of mappings:

  • One-to-One Mapping – A field that directly maps to another field that is identical.
  • One-to-Many Mapping – A single field from one system will map to multiple fields from another.
  • Many-to-One mapping – Multiple fields from a source map to a single field in the destination.
  • Transformation Mapping – The field that requires transformation logic in mapping (e.g., date formats).

You will want to use mapping tables or spreadsheets to document each match, including transformation rules and notes as needed.[3]

5. Use Data Dictionary Mapping Tools or Services

Manual mapping is very error-prone because of human experiences, especially in large and complicated datasets. You might want to consider using a dedicated data dictionary mapping tool or using a professional data dictionary mapping service.

  • Most data dictionary mapping tools will offer some or all the following features:
  • Metadata harvesting
  • Mapping recommendations
  • Impact assessment
  • Visualization dashboards
  • Audit trails [5]

If you do choose to outsource to a data dictionary mapping service, you want to ensure the vendor has industry standards and compliance experience in your context.

6. Use Human-in-the-Loop (HITL) Systems

It is important to tester everything (even if you don’t) before deploying! Test for:

  • Accuracy TBD
  • completed data
  • Correctness of transformations
  • Data types are compatible
  • Referential Integrity

Ask business analysts or appropriate subject matter experts to check that mapped data is contextually correct. [2]

7. Document the Mapping Process

The documentation you provide should capture the following:

  • Mapping logic.
  • Transformation rules.
  • Field level notes.
  • Test results.
  • Change history.

Documentation provides both the clarity and transparency you need when applying data mappings to your systems, it will also make future audits or updates simpler. [4]

8. Manage and Update Each Time

Data dictionaries and mappings are not static. Data mappings should change as systems evolve. Form a governance model to regularly review and update data mappings.[5]

Determine triggers such as:

Typical Issues with Data Dictionary Mapping

Despite the significance of data dictionary mapping there are many obstacles faced by organizations when considering data dictionary mapping.

  • Lack of Metadata Documentation: Definitions of metadata may not exist or are incomplete or out-of-date.
  • Complex Legacy Systems: Older systems may be developed differently to modern systems with respect to mapping data.
  • Inconsistent Naming Conventions: Teams using different words to articulate the same idea or concept.
  • Count and Complexity of the Data: There could be a high volume of fields (e.g. dozens if not hundreds of fields) and many relationships in the data.
  • Limited expertise: There are very few skilled resources in the areas of data mapping as well as creating and managing metadata documentation.

Using experienced data dictionary mapping providers can assist with many of the problems mentioned above by providing tools; to assist as well as frameworks and domain knowledge related to dictionary mapping. [1] [3]

Conclusion

Conclusion

Data dictionary mapping is an important first step to successful data integration. Whether you are merging, building a data warehouse or performing live data synchronization, without the appropriate plans mapped, your chances of being successful are slim.

Utilizing a structured approach, and experts on data dictionary mapping, organizations can mitigate significant integration risk, improve data quality, and support better decision-making.

References

References

  1. Rashid, S. M., McCusker, J. P., Pinheiro, P., Bax, M. P., Santos, H., Stingone, J. A., Das, A. K., & McGuinness, D. L. (2020). The Semantic Data Dictionary – An Approach for Describing and Annotating Data. Data intelligence2(4), 443–486. https://pubmed.ncbi.nlm.nih.gov/33103120/
  2. Boeckhout, M., Zielhuis, G.A. & Bredenoord, A.L. The FAIR guiding principles for data stewardship: fair enough? Eur J Hum Genet26, 931–936 (2018). https://www.nature.com/articles/s41431-018-0160-0#citeas
  3. Sharma, D. K., Solbrig, H. R., Prud’hommeaux, E., Pathak, J., & Jiang, G. (2017). Standardized Representation of Clinical Study Data Dictionaries with CIMI Archetypes. AMIA … Annual Symposium proceedings. AMIA Symposium2016, 1119–1128.https://pubmed.ncbi.nlm.nih.gov/28269909/
  4. P. Uhrowczik, “Data Dictionary/Directories,” in IBM Systems Journal, vol. 12, no. 4, pp. 332-350, 1973, doi: 10.1147/sj.124.0332.
  5. Wilkinson, M., Dumontier, M., Aalbersberg, I. et al.The FAIR Guiding Principles for scientific data management and stewardship. Sci Data 3, 160018 (2016). https://doi.org/10.1038/sdata.2016.18

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