SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45c34913321b7745b6d4ffbe763f0bff371eea551943f274f1202fef1f02383b' 
  AND token = 'EXma5Umm6egmhs7Pqu4t44vRyUKRw4y2g6j7RP4pJWc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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