Fig. 1

Simplified schema diagram of the Volcanic Hazard Maps Database. Main data tables and link tables are shown (purple and gray, respectively). Column names are followed by the data type with the length in parentheses (e.g., VARCHAR(50)). The data type TINYINT is used to indicate yes/no values. Definition tables, which define the options available for a particular column, are not shown to make the schema readable. Each definition table consists of an ID or code as the primary key, a short description, and a long description