android操作SQLite增删改减实现代码

//创建表
public Boolean createTable(){
sqliteDatabase db=dbHelper.getWritableDatabase();
String sql="create table IF NOT EXISTS "+TABLE_NAME+"(ID INTEGER PRIMARY KEY,name varchar,age integer)";
try{
db.execsql(sql);
return true;
}catch(sqlException eX){
Log.d(tag,"create table failure");
return false;
}
}
//添加数据
public Boolean addData(){
String name=etname.getText().toString();
String age=etage.getText().toString();
sqliteDatabase db=dbHelper.getWritableDatabase();
String sql="insert into "+TABLE_NAME+"(name,agE) values ('"+name+"','"+age+"')";
try{
db.execsql(sql);
return true;
}catch(sqlException eX){
Log.d(tag,"add data failure");
return false;
}
}
//修改
public Boolean updateData(){
sqliteDatabase db=dbHelper.getWritableDatabase();
String sql="update "+TABLE_NAME+" set age='2' where name like 'cb'";
Object[] bindArgs={"cb"};
try{
db.execsql(sql,bindArgs);
return true;
}catch(sqlException eX){
Log.d(tag,"update data failure");
return false;
}
}

//查询 public void SELEctData(){
sqliteDatabase db=dbHelper.getReadableDatabase();
String[] columns={"name"};
cursor cursor=db.query(TABLE_NAME,null,null);
String names="";
while(cursor.moveToNext()){
int c=cursor.getcolumnIndexOrThrow("Name");
String name=cursor.getString(c);
//< = >
//String name=cursor.getString(0);//只查询了一列
if(names==""){
names=name;
}else{
names=names+"\n"+name;
}
}
tvname.setText(names);
//另外一种查询方法
//String sql="SELEct name from "+TABLE_NAME;
//Curosr cursor=db.rawQuery(sql,null);
}