select查询不为我工作的android

Question

此代码的工作对我来说：

SQL = "SELECT _id,Fname,Lname,Phone,Car,CarNum,PicNum from MEN order by Lname,Fname"; 
. 
. 
public void update_list(String NN) { 
     c = db.rawQuery(NN, null); 
     startManagingCursor(c); 

     String[] from = new String[]{"_id","PicNum","Fname","Lname","Car","CarNum" }; 
     int[] to = new int[]{ R.id._id,R.id.MyPic,R.id.Fname ,R.id.Lname,R.id.Car,R.id.CarNum }; 
     SimpleCursorAdapter notes = new SimpleCursorAdapter (this, R.layout.my_list, c, from, to); 
     setListAdapter(notes); 


setListAdapter(new SimpleCursorAdapter(this, R.layout.my_list, c, from,to) { 

，但如果我的查询是这样的：

SQL = "SELECT _id,Fname + Lname as Fname,Lname,Phone,Car,CarNum,PicNum from MEN order by Lname,Fname"; 

我在列FNAME得到0。

Answer 1

我想你使用的是不正确的连接运算符。请参考下面的问题。

How to concatenate strings with padding in sqlite