SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd98c17874c81cdae8c4159da836fd55bf24796f1caa7b18b7d5e47fc92a7363d' 
  AND token = 'TN4mbqx2KK26/Dymt1Yl6ReV15ADzvwjUVUR/p/OCGo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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