In Gemini a number can be of the following types: INTEGER, DOUBLE, DECIMAL
- name: id
- name: weight
- name: price
- name: quantity
As the name suggests, integer and double are respectively numbers without and with floating point unit. Decimal instead should be used we you need to represent a number with perfect accuracy, for example to handle money and financial data. Basically they should be used when you don't want an approximation for your number, as the double data type does.
The purpose of Gemini is to create REST APIs and its GUI. If your service need a more control on the data types you could re-map the Gemini types in what you want in the data driver.
Future releases will introduce validations and checking for numbers. For example min or max or inside some ranges.