Data types are simply categories assigned by a data tool or programming language that provide information about the range of possibilities for the values that data can have. There are many different data types in the industry, but the three main categories are:
- Text - typically referred to as a string, and can have a variable (e.g. a comment box on a website) or fixed size (e.g. 2-Letter Country Code)
- Numbers - different types include integer (round numbers), numeric (decimal values) and boolean (0 or 1)
- Dates - describe dates in time, often stored in a “year-month-day” format
Data types have a big impact on data tool functionality and performance, and can lead to incorrect interpretation of results in some cases. For instance:
- Financial transaction data saved as Integers instead of Numeric would round to the nearest dollar
- Dates saved as a Timestamp without knowing timezone would be impossible to convert