java - comparing a input string to string in a database -

i'm studying android studio , started databases week. little app. simple. user enters string , presses button in first activity. string sent second activity compared values in database , display ones similar:

public class drinkcategoryactivity extends listactivity { public static final string extra_message = "message"; private sqlitedatabase db; private cursor cursor; private cursor newcursor;  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     intent intent = getintent();     string messagetext = intent.getstringextra(extra_message);     //setcontentview(r.layout.activity_drink_category);     listview listdrinks = getlistview();     try{         sqliteopenhelper starbucksdatabasehelper = new starbucksdatabasehelper(this);         db = starbucksdatabasehelper.getreadabledatabase();         /*             select _id, name drinks;          */         cursor = db.query("drink",                     new string[]{"_id", "name"},                     null, null, null, null, null);         newcursor = cursor.equals(messagetext);         cursoradapter listadapter = new simplecursoradapter(this,                 android.r.layout.simple_list_item_1,                 cursor,                 new string[]{"name"},                 new int[]{android.r.id.text1},                 0);          listdrinks.setadapter(listadapter);      }catch (sqliteexception ex){         toast toast = toast.maketext(this, "database unavailable",                 toast.length_long);         toast.show();     } 

i have been looking on web can not find explanation. database

this database drinks

public class starbucksdatabasehelper extends sqliteopenhelper{     add varaible db name     private static final string db_name = "starbucks";      version of database     private static final int db_version = 1;      starbucksdatabasehelper (context context){         super(context, db_name, null, db_version);     }      @override     public void oncreate(sqlitedatabase db) {         db.execsql("create table drink ("                 + "_id integer primary key autoincrement, "                 + "name text, "                 + "description text, "                 + "image_resource_id integer);");      insert data         insertdrink(db, "soy latte", "esspresso , steamed soy milk", r.drawable.latte);         insertdrink(db, "mocaccino", "esspresso, hot milk, steamed milk foam, , cocoa", r.drawable.cappuccino);         insertdrink(db, "american", "drip coffee", r.drawable.filter);     }      private static void insertdrink (sqlitedatabase db,                                      string name,                                      string description,                                      int resourceid){         contentvalues drinkvalues = new contentvalues();         drinkvalues.put("name", name );         drinkvalues.put("description", description);         drinkvalues.put("image_resource_id", resourceid);           db.insert("drink", null, drinkvalues);     }     @override     public void onupgrade(sqlitedatabase db, int oldversion, int newversion) {      } 

try query instead if want row containing messagetext in start, middle or end should retrieved -

cursor = db.query("drink", new string[]{"_id", "name"}, "name %?%", new string[]{messagetext}, null, null, null);