Best practices for creating a data model

Introduction to data modeling

When creating a data model for an application in Eximee, you should follow principles that will make the system easier to maintain and ensure data consistency across the entire organization. A well-designed model is the foundation of efficient information flow between the user interface and the process engine.

Key naming standards

An effective data model should be intuitive. When designing keys, follow the technical standards below:

Aspect	Rule	Example (Good)	Example (Bad)
Format	Use camelCase, a single language (English), no PL characters or spaces.	startDateOfEmployment	Start_Date
Boolean logic	Start with is or has.	isPoliticallyExposed	is_pep
The "of" pattern	Use the "of" construction for clarity of context.	countryOfResidence	residenceCountry
Identifiers	Avoid generic id. Add business context.	customerId	id

Principles for designing structure and development

The following rules define the approach to the model architecture and its evolution over time:

Rule	Description and business rationale
Hierarchy and structure	The tree structure must reflect the natural hierarchy of business data. Group fields into semantic objects (e.g. customerData.name or registerAddress). This makes it easier to map entire structures to services and increases model readability.
Data vs. Calculations	Store source data (e.g. dates), not variable or derivable values (e.g. age). If a calculation is necessary, add it as a separate field dynamically fed by a provider.
Avoid duplication	Before adding a field, check whether similar information already exists. Different objects (e.g. addresses) should share the same internal key names (e.g. streetName), to maintain technological consistency.
YAGNI strategy	Do not model structure "for later". Add only the fields that are actually required at the current stage of the process. An excessive model makes analytics harder.
Reusability	When designing a new structure, treat existing models in other applications as a reference point. Keep consistent naming for the same concepts across the entire organization.
Requirement updates	With every modification of the BPMN process (e.g. adding or removing a step) or form (e.g. adding a new data section), perform an impact analysis on the data model. Lack of synchronization is the most common cause of errors.

Documentation and technical parameters

The data model in Eximee is not only a structure, but also metadata that facilitates integration and maintenance:

Parameter	Rule and best practices
Attribute docs	Document the business meaning and context of keys and providers. In the application documentation, use full dot notation (e.g. customerData.address.street).
Value defaultValue	Allows assigning a default value (e.g. the flag false), when the sources do not provide data. This prevents errors of type null pointer.
Multiplicity	Parameters must precisely reflect the business logic. For required fields Min=1. For lists of unlimited length, use Max=null.
Source logic	Document the order and mappings of providers. Remember - the first source that returns a value other than nullnull, takes priority.

Common mistakes and how to avoid them

Below is an overview of the most common mistakes made when creating and using a data model - their causes, effects, and how to avoid them.

Error	Cause	Effect	Solution
Missing form binding	The "Data model key" was not set in the component.	Data is not being saved (the field is empty after refresh).	Set the key in the component properties by entering the exact field key from the data model. After saving the form, the component will save its value to that field, and when launched it will retrieve the existing value from the model.
Typos and name mismatches	Typing names manually in the "Data model key" option.	The component will not connect to the correct field in the data model - the value will not be saved to the model.	"Use the copy icon next to the key in the data model.
Incorrect use of arrays	Omitting index notation (e.g. products.price).	Syntax without [] or an index is invalid and will cause an error preventing the form from launching.	In repeatable sections, use the notation products[].price.
Invisible data model	No artifact in the application.	The model has not been initialized.	Use the "Initialize data model" button in the application's "Data model" tab.