SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ceea99e38e7e6a381d43d8b665642efdf8785724d5c369e6b060f0edc69700c1' 
  AND token = 'kiLlsk354XzWwLiuKDRIRODGWGh85F4wE5Y/iUIeIjE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}