title: ESP8266 with Firebase (firebase-arduino-master) adds unique key
body: <p>I have a problem with saving data in Firebase realtime and sending from ESP8266. I use firebase-arduino-master library. I want to send the soil moisture information from ESP8266 to Firebase periodically. Connecting works, data is being transferred, but in the database I can see an automatically added prefix - a unique key.
  <a href="https://i.stack.imgur.com/YmOSl.png" rel="nofollow noreferrer">enter image description here</a></p>
  <p>My code:</p>
  <pre><code>    void setup() 
  {
    Serial.begin(9600);
    delay(1000);                    
    WiFi.begin(WIFI_SSID, WIFI_PASSWORD);                               
    Serial.print(&quot;Connecting to &quot;);
    Serial.print(WIFI_SSID);
    while (WiFi.status() != WL_CONNECTED) 
    {
      Serial.print(&quot;.&quot;);
      delay(500);
    }
    Serial.println();
    Serial.print(&quot;Connected to &quot;);
    Serial.println(WIFI_SSID);
    Serial.print(&quot;IP Address: &quot;);
    Serial.println(WiFi.localIP());                               //prints local IP address
    Firebase.begin(FIREBASE_HOST, FIREBASE_AUTH);                 // connect to firebase
    Serial.println(Firebase.success());
    Serial.println(&quot;OK&quot;);
    timeClient.begin();
    delay(2000);
  }
  
  void loop() {
    timeClient.update();
    float moisture_percentage;
  
    moisture_percentage = map(analogRead(sensor_pin), 696, 328, 0, 100);
  
    unsigned long epochTime = timeClient.getEpochTime();
  
  //Get a time structure
    struct tm *ptm = gmtime ((time_t *)&amp;epochTime); 
    int monthDay = ptm-&gt;tm_mday;
    int currentMonth = ptm-&gt;tm_mon+1;
    int currentYear = ptm-&gt;tm_year+1900;
    //Print complete date:
    String currentDate = String(currentYear) + &quot;-&quot; + String(currentMonth) + &quot;-&quot; + String(monthDay);
    Serial.print(currentDate);
    Serial.print(&quot; &quot;);
    Serial.print(timeClient.getFormattedTime());
    Serial.print(&quot; - &quot;);
    Serial.print(moisture_percentage);
    Serial.println(&quot;%&quot;);
    float m = moisture_percentage;
    String fireMoist = String(currentDate) + String(&quot; &quot;) + String(timeClient.getFormattedTime()) + String(&quot; &quot;) + String(moisture_percentage) + String(&quot;%&quot;);                  //Moisture integer to string conversion
    Firebase.pushString(&quot;MOIST&quot;, fireMoist);                                   //setup path to send Moisture readings
   
    delay(2000);
  }
  </code></pre>
  <p>I want to know how remove the prefix, unique key.
  Thanks for helping!</p>