Basics

Database Management Systems

• MySQL: run on servers separate from those running a website
• PostgreSQL: run on servers separate from those running a website
• SQLite: a lighter-weight system that can store all of its data in a single file

Column Types

• TEXT: For strings of text (Ex. a person’s name) NUMERIC: A more general form of numeric data (Ex. A date or boolean value)
• INTEGER: Any non-decimal number (Ex. a person’s age)
• REAL: Any real number (Ex. a person’s weight)
• BLOB (Binary Large Object): Any other binary data that we may want to store in our database (Ex. an image)

Constraints

• CHECK: Makes sure certain constraints are met before allowing a row to be added/modified
• DEFAULT: Provides a default value if no value is given
• NOT NULL: Makes sure a value is provided
• PRIMARY KEY: Indicates this is the pimary way of searching for a row in the database
• UNIQUE: Ensures that no two rows have the same value in that column.