in Sources/XCMetricsBackendLib/Statistics/Repositories/Migrations/CreateDayCount.swift [24:30]
func prepare(on database: Database) -> EventLoopFuture<Void> {
database.schema(DayCount.schema)
.field("day", .date, .identifier(auto: false))
.field("build_count", .int, .required)
.field("error_count", .int, .required)
.create()
}