I do not get anything from php on android

Good afternoon, I have a problem. I get to fetch the information all I have in the table, but when I change the code so that the information of a certain error person appears to me and returns no value value for the android. I'm new to android so please help. If you can post the corrected code Thanks.

Functional PhP code (Returns the entire table (this is not the goal)): Here it works:  The log: jsonResult :: {"info": [{"NProcess": "467", "QueryDate": "11-7-2014", "QueryTime": "14:41" / p>

  <?php
       $host     = "XXXXX";
       $username = "XXXXX";
       $password = "XXXXX";
       $db_name  = "android";

       $con = mysql_connect("$host", "$username", "$password") or die("cannot connect");
       mysql_select_db("$db_name") or die("cannot select DB");
       $tec    = $_POST['Tecnica'];
       $sql    = "select * from info order by Registo desc";
       $result = mysql_query($sql);
       $json   = array();

       if (mysql_num_rows($result)) {
       while ($row = mysql_fetch_assoc($result)) {
           $json['info'][] = $row;
       }
      }
     mysql_close($con);
     echo json_encode($json);
   ?> 

PhP code that I want to work on (goal: just show the information of the person who logs in): The PROBLEM of this code is that it sends me nothing to android. The log: jsonResult :: []

      <?php
      $host     = "XXXXX";
      $username = "XXXXXX";
       $password = "XXXXXX";
      $db_name  = "android";

       $con = mysql_connect("$host", "$username", "$password") or die("cannot connect");
      mysql_select_db("$db_name") or die("cannot select DB");
      $tec    = $_POST['Tecnica'];
      $sql    = "select * from info where Tecnica = $tec order by Registo desc";
      $result = mysql_query($sql);
      $json   = array();

       if (mysql_num_rows($result)) {
        while ($row = mysql_fetch_assoc($result)) {
          $json['info'][] = $row;
        }
         }
        mysql_close($con);
         echo json_encode($json);
       ?> 

And my class (without changing the class, works the 1st php but not the second):

public class ReadInfo extends Activity {

ListAdapter adapter;
String NTECNICA;
private String jsonResult;
private String url = "http://www.cresceranorte.com/WebService/info.php";
private ListView listView;

@Override
protected void onCreate(Bundle savedInstanceState) {


    super.onCreate(savedInstanceState);

    setContentView(R.layout.read_info);
    Bundle extras = getIntent().getExtras();
    if (extras != null) {

        Intent intent = getIntent();
        NTECNICA=  intent.getExtras().getString("NTECNICA");
        Log.d("Atencao NTecnica", NTECNICA);

        //Toast.makeText(MainMenu.this, value, Toast.LENGTH_SHORT).show();
    }
    listView = (ListView) findViewById(R.id.list);
    accessWebService();

}




@Override
public boolean onCreateOptionsMenu(Menu menu) {

    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}
public void addInfo(View v)
        {
                Intent i = new Intent(ReadInfo.this, AddInfo.class);

            i.putExtra("NTECNICA",NTECNICA);
                startActivity(i);
            }


public void actList(View v)
{
    Intent i = new Intent(ReadInfo.this, ReadInfo.class);
    startActivity(i);
}




// Async Task to access the web
public class JsonReadTask extends AsyncTask<String, Void, String> {

    @Override
    protected String doInBackground(String... params) {


        String post_Tecnica=NTECNICA;

        HttpClient httpclient = new DefaultHttpClient();
        HttpGet ger = new HttpGet(url);
        ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
        nameValuePairs.add(new BasicNameValuePair("Tecnica", post_Tecnica));

        String oo;
        oo = String.valueOf(nameValuePairs);
        Log.d("HTTP: ", oo);
        try {

            HttpResponse response = httpclient.execute(ger);

            oo = String.valueOf(response);
            Log.d("HTTPResponse: ", oo);
            jsonResult = inputStreamToString(
                    response.getEntity().getContent()).toString();
            Log.d("Atencao jsonResult: ", jsonResult);

        }

        catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    private StringBuilder inputStreamToString(InputStream is) {
        String rLine = "";
        StringBuilder answer = new StringBuilder();
        BufferedReader rd = new BufferedReader(new InputStreamReader(is));

        try {
            while ((rLine = rd.readLine()) != null) {
                answer.append(rLine);
            }
        }

        catch (IOException e) {
            // e.printStackTrace();
            Toast.makeText(getApplicationContext(),
                    "Error..." + e.toString(), Toast.LENGTH_LONG).show();

        }
        return answer;
    }

    @Override
    protected void onPostExecute(String result) {
        ListDrwaer();
    }
}// end async task

public void accessWebService() {
    JsonReadTask task = new JsonReadTask();
    // passes values for the urls string array
    task.execute(new String[] { url });
}

// build hash set for list view
public void ListDrwaer() {

    List<Map<String, String>> consultasList = new ArrayList<Map<String, String>>();


    try {

        JSONObject jsonResponse = new JSONObject(jsonResult);
        JSONArray jsonMainNode = jsonResponse.optJSONArray("info");


        for (int i = 0; i < jsonMainNode.length(); i++) {
            JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
            String name = jsonChildNode.optString("NProcesso");
            String number = jsonChildNode.optString("DataConsulta");
            String dat = jsonChildNode.optString("HoraConsulta");
            String outPut = "Nº Processo: "+ name + "\n" + "Data: "+ number + "\n" + "Hora: "+ dat + "\n";
            consultasList.add(createEmployee("employ", outPut));
        }
    } catch (JSONException e) {
        Toast.makeText(getApplicationContext(), "Error ListDrwaer " + e.toString(),
                Toast.LENGTH_SHORT).show();
        Log.d("Error ListDrwaer  ", e.toString());
    }

    SimpleAdapter simpleAdapter = new SimpleAdapter(this, consultasList,
            android.R.layout.simple_list_item_1,
            new String[] { "employ" }, new int[] { android.R.id.text1 });
    listView.setAdapter(simpleAdapter);
}

private HashMap<String, String> createEmployee(String name, String number) {
    HashMap<String, String> employeeNameNo = new HashMap<String, String>();
    employeeNameNo.put(name, number);
    return employeeNameNo;
}

}