CREATE TABLE IF NOT EXISTS location_latest (
 device VARCHAR(64) CHARACTER SET ascii COLLATE ascii_bin PRIMARY KEY,
 latitude DECIMAL(10,7) NOT NULL,
 longitude DECIMAL(11,7) NOT NULL,
 accuracy_m DOUBLE NULL,
 measured_at BIGINT UNSIGNED NOT NULL,
 received_at DATETIME NOT NULL,
 regions_json TEXT NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;