SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a2902f7fd3e1a7d073f24c4ed80e70d6b9af11f955e2f8b115379c20879b899' 
  AND token = 'dqzofGaQkaK5f0qczIqwYO3mCrIVx3wMVldXKau1p5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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