SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f44ccc237bd6f67f25b300dd7b44bdf9b38f7513196478edfcafb2799799756b' 
  AND token = 'pCt9P6MDGhTXDV6VI3R6HyhSyZht1lJqRYHCbHIYGw0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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