Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b28b43869e349bfe40c440e477d6ba06d8d1b5b16561ca327ee3f5a665ef48a' 
  AND token = 'kAsvcjrN192yKWGQVjv2TNO4EGMkOt5mp3Idj/nWRe8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}