SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0bf9ce1351c4f56f0da0b112173e05407457a942ad709cfd704ae88165c0b584' 
  AND token = 'WbHxQLx6S95JdB/Nyp+zlBWPJkPannpSyNvQYdSQnRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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