MySQL での MAC アドレスの保存

CREATE TABLE devices (
    id          INT AUTO_INCREMENT PRIMARY KEY,
    mac_address VARCHAR(17),
    hostname    VARCHAR(255)
);

INSERT INTO devices (mac_address, hostname) VALUES
    ('08:00:2b:01:02:03', 'server-01'),
    ('08-00-2B-01-02-04', 'server-02');  -- different format, uppercase

CREATE TABLE devices (
    id          INT AUTO_INCREMENT PRIMARY KEY,
    mac_address BINARY(6),
    hostname    VARCHAR(255)
);

-- No built-in conversion — typically done in application code
-- or manually with UNHEX after stripping colons
INSERT INTO devices (mac_address, hostname)
VALUES (UNHEX(REPLACE('08:00:2b:01:02:03', ':', '')), 'server-01');

SELECT LOWER(INSERT(INSERT(INSERT(INSERT(INSERT(
    HEX(mac_address), 3,0,':'), 6,0,':'), 9,0,':'), 12,0,':'), 15,0,':'))
AS mac FROM devices;

INSTALL EXTENSION vsql_network_address;

CREATE TABLE devices (
    id          INT AUTO_INCREMENT PRIMARY KEY,
    mac_address MACADDR,
    hostname    VARCHAR(255)
);

-- All three formats parse to the same stored value
INSERT INTO devices (mac_address, hostname) VALUES
    (macaddr_from_string('08:00:2b:01:02:03'), 'server-01'),   -- colon notation
    (macaddr_from_string('08-00-2b-01-02-04'), 'server-02'),   -- hyphen notation
    (macaddr_from_string('0800.2b01.0206'),    'server-03');   -- Cisco dot notation

-- Always returns normalized colon format
SELECT macaddr_to_string(mac_address), hostname FROM devices;

08:00:2b:01:02:03   server-01
08:00:2b:01:02:04   server-02
08:00:2b:01:02:06   server-03

-- Find all devices from the same manufacturer. CAST to CHAR here works
-- around a known issue where GROUP BY truncates this expression's result
-- to the underlying type's stored length instead of the full string.
SELECT CAST(macaddr_to_string(macaddr_trunc(mac_address)) AS CHAR(20)) AS oui,
       COUNT(*) AS device_count
FROM devices
GROUP BY CAST(macaddr_to_string(macaddr_trunc(mac_address)) AS CHAR(20))
ORDER BY device_count DESC;

-- Filter by manufacturer OUI
SELECT hostname, macaddr_to_string(mac_address)
FROM devices
WHERE macaddr_trunc(mac_address) = macaddr_from_string('08:00:2b:00:00:00');

-- Sort devices by MAC address
SELECT hostname, macaddr_to_string(mac_address)
FROM devices
ORDER BY mac_address;

-- Find a specific device
SELECT hostname FROM devices
WHERE mac_address = macaddr_from_string('08:00:2b:01:02:03');

CREATE TABLE modern_devices (
    id          INT AUTO_INCREMENT PRIMARY KEY,
    mac_address MACADDR8
);

INSERT INTO modern_devices VALUES
    (1, macaddr8_from_string('08:00:2b:01:02:03:04:05'));

SELECT macaddr8_to_string(mac_address) FROM modern_devices;
-- Returns: 08:00:2b:01:02:03:04:05