Android DB 사용하기 예제
Android 에서 DB 를 사용하는 예제 (name / contents 2개의 column)
public class AndroidDBHelper extends SQLiteOpenHelper{
public AndroidDBHelper(Context context) {
super(context, "android.db3", null,1);
}
@Override
public void onCreate(SQLiteDatabase db) {
String query="create table androidtable(name VARCHAR(30),contents VARCHAR(100))";
db.execSQL(query);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
public class AndroidDB {
SQLiteDatabase db;
Context context;
public AndroidDB(Context context){
AndroidDBHelper dbhelper= new AndroidDBHelper(context);
this.db=dbhelper.getWritableDatabase();
}
public void insertExample(String name, String contents){
String query="insert into androidtable (name,contents) VALUES ('"+name+"','"+contents+"')";
try{
db.execSQL(query);
}catch(Exception e){
e.printStackTrace();
}
db.close();
}
public void deleteExample(name){
String query="Delete From androidtable Where name = '"+name+"';
try{
db.execSQL(query);
}catch(Exception e){
e.printStackTrace();
}
db.close();
}
public void updateExample(String name, String contents){
String query = "update androidtable set name='"+name+"' , contents='"+contents+"' where name = "+name+";
try{
db.execSQL(query);
}catch(Exception e){
e.printStackTrace();
}
db.close();
}
public HashMap<String, String> selectExample(){
HashMap<String, String> map= new HashMap<String, String>();
String sql="select contents from androidtable";
Cursor c=db.rawQuery(query, null);
if( c.moveToFirst() ){
do{
map.put(c.getString(0),"");
}while( c.moveToNext());
}
c.close();
db.close();
return map;
}
}
사용할때
HashMap<String, String> map;
AndroidDB db= new AndroidDB(this);
map = db.selectExample();