SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '42e0ce3276552c86980e864ae8cdbdfd870a79759a991413cef34cdcec970b72' 
  AND token = 'BTJqAwSl9G6vPJ7yoBF9B20zHL6GQyVmIY/BM1fysKk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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