The RESO Data Dictionary is a living reference source meant to standardize MLS data. It is discussed and often updated monthly in the Data Dictionary Workgroup.
Two core assumptions of the dictionary include extensibility and omissibility.
Extensibility is the ability to extend the dictionary with your own local fields. For example, a field called MilesToVolcano is not be applicable to most geographies, and is not included in the Data Dictionary. But if it’s useful in Hawaii, local organizations can use that extended local custom field along with standard fields.
Omissibility is the ability to only use the portions of the Data Dictionary that are applicable to your business needs. Just because a field is in the dictionary, that doesn’t mean the field must be in your data set. For example, Ocean may be a useful value for the View lookup in California, but it doesn’t need to be included in Nebraska’s data set.
You are, however, required to locate field name commonality to be in conformance for certification. If your Price field is really a list price, then you must use the Data Dictionary Standard Name of ListPrice as your field name.
This raises an important distinction between Standard Names vs. Display Names (aka labels) in the dictionary. RESO certification tests against Standard Names, not Display Names.
Standard Names, which are overwhelmingly written in PascalCase (e.g., TaxAnnualAmount, no spaces), are the data field names needed for technical interoperability. Display Names appear as field labels for reports or listing input (e.g., Tax Annual Amount, spaces included). Display Names are your choice but aligning them to Standard Names is recommended.
Read more at the Larson Consulting LLC blog, written by Rob Larson, RESO Data Dictionary Workgroup Chair.
