SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0174e2cc2089ce5688c3de00339061be5e88eb7b4aac466c52907e0e8eb1e63b' 
  AND token = 'Ekh8/lEXHfvLZHNTc8DIAVM6rbjtv8jAqNcIXj7dCxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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