java - How to display only selected data from database in Android Studio -

my program designed search database specific name entered, program display row of specific name. however, code unable display specific data. have tried many kind of ways unable solve problem. php code below:

    <?php     $con = mysql_connect('mysql17.000webhost.com', 'a2634311_minzhe', 'mzrules0118');      if (!$con)       {       die('could not connect: ' . mysql_error());       }      mysql_select_db("a2634311_gdp", $con);     $result = mysql_query("select * groupdesign");     while($row = mysql_fetch_assoc($result))       {         $output[]=$row;       }     print(json_encode($output));      mysql_close($con);     ?> 

my activity code below:

    import android.app.activity;     import android.content.context;     import android.content.intent;     import android.content.sharedpreferences;     import android.os.asynctask;     import android.os.strictmode;     import android.support.v7.app.actionbaractivity;     import android.os.bundle;     import android.util.log;     import android.view.layoutinflater;     import android.view.view;     import android.view.viewgroup;     import android.widget.baseadapter;     import android.widget.button;     import android.widget.listview;     import android.widget.textview;     import android.widget.toast;      import org.json.jsonarray;     import org.json.jsonexception;     import org.json.jsonobject;      import java.io.inputstream;       public class patientlocation extends actionbaractivity {          private listview patientlocationlistview;          @override         protected void oncreate(bundle savedinstancestate) {               strictmode.threadpolicy policy = new         strictmode.threadpolicy.builder().permitall().build();             strictmode.setthreadpolicy(policy);              this.patientlocationlistview = (listview)         this.findviewbyid(r.id.listview4);              new location().execute(new api_connector());         }          public void setlistadapter(jsonarray jsonarray) {              sharedpreferences settings = getsharedpreferences("myprefrences", context.mode_private);             string name = settings.getstring("name", "");             this.patientlocationlistview.setadapter(new         patientadapter(jsonarray,name, this));         }          private class location extends asynctask<api_connector, long, jsonarray> {             @override             protected jsonarray doinbackground(api_connector... params) {                  //it executed on background thread                  return params[0].getpatientlocation();             }              @override             protected void onpostexecute(jsonarray jsonarray) {                 // check null                 if (jsonarray != null) {                     // pass array adapter if not null                     setlistadapter(jsonarray);                 } else {                     toast.maketext(patientlocation.this, "null array returned", toast.length_short).show();                 }               }         }     }      class patientadapter extends baseadapter {          private jsonarray dataarray;         private activity activity;         string pname;          private static layoutinflater inflater = null;          public patientadapter(jsonarray jsonarray, string name, activity a) {             this.dataarray = jsonarray;             this.activity = a;             this.pname = name;              inflater = (layoutinflater)         this.activity.getsystemservice(context.layout_inflater_service);         }          @override         public int getcount() {             return this.dataarray.length();         }          @override         public object getitem(int position) {             return position;         }          @override         public long getitemid(int position) {             return position;         }          @override         public view getview(int position, view convertview, viewgroup parent) {              string patientname,patientlocation;             //set convert view if null             listcell cell = new listcell();             if (convertview == null) {                 convertview = inflater.inflate(r.layout.activity_position, null);                  cell.patient_name = (textview)         convertview.findviewbyid(r.id.textview30);                 cell.patient_location = (textview) convertview.findviewbyid(r.id.textview31);                 convertview.settag(cell);             }             else {                 cell = (listcell) convertview.gettag();             }             //change data of cell              try {                 for(int i=0;i<dataarray.length();i++) {                     jsonobject jsonobject = this.dataarray.getjsonobject(i);                     if(pname == jsonobject.getstring("name")) {                         patientname = jsonobject.getstring("name");                         patientlocation = jsonobject.getstring("location");                          cell.patient_name.settext(patientname);                         cell.patient_location.settext(patientlocation);                     }                  }             }             catch (jsonexception e) {                 e.printstacktrace();             }              return convertview;         }          private class listcell {             private textview patient_name;             private textview patient_location;         }      } 

where clause in query in php code? need set conditions match specific name in query if want search 'abcd' query should select * groupdesign column_name = "abcd". return records contanis value "abcd" database