Why data types matter

Concepts: sqlBasicTypes

Data types are not just labels. They fundamentally determine how your data is stored, processed, and queried. The database uses your type choice to decide everything from how much disk space to use, to whether math operations are allowed. SQL databases organize data into three fundamental categories. Every other type is a specialization of these: Type Mismatch Consequences Choosing the wrong type leads to unexpected behavior in operations like arithmetic and sorting. Arithmetic Proves the Type The type system enforces what operations are legal. Storing a number as text disables arithmetic and changes sort order, so the database treats "9" as greater than "10" alphabetically. Type mismatches are among the most common sources of data pipeline bugs. Catching them early at schema design time i