android - 带有where子句的sqlite在android中不起作用

Question

Log.e("Thinhdt1", qb.buildQuery(new String[] { "sum(money)" }, 
             "category = ?", new String[] {category}, null, null, null, null));

     Cursor mCursor = mDb.query(
         "Exchange",
         new String[] { "sum(money)" },
         "category = ?" , 
         new String[] {category},
         null,
         null,
         null
         );

登录 logcat() : SELECT sum(money) FROM Exchange WHERE (category = ?)

请找到错误帮助我。谢谢 。

Answer 1

尝试

Cursor mCursor = mDb.query(
     "Exchange",
     new String[] { "sum(money) as sum" },
     "category = ?" , 
     new String[] {category},
     null,
     null,
     null
     );