SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92eb98cc83562a9539baa783863e4265d1f3c6253e0448d2653521ebc712e1b5' 
  AND token = 'XkC+A7A6PokQco7btlcskcJdMgOaaDqwW9YW+5lCiek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}