返回整数数组的SQLite查询数据

Question

您好任何帮助都会非常感谢！ 我的数据库表中有3个字段

public static final String colExpID = "ExpenseID";      
public static final String colExpExpense = "ExpenseDisc";
public static final String colExpAmount = "Amount";

我查询数据的方法

public Integer[] queryHouse() {
        // TODO Auto-generated method stub
        String[] columns = new String[]{colExpID,colExpExpense,colExpAmount};
        Integer[] Result = new Integer[]{};     
        Cursor c = ourDatabase.query(ExpenseTable, columns, null, null, null, null, null);
        int iExpense = c.getColumnIndex(colExpExpense);
        int iAmount = c.getColumnIndex(colExpAmount);
        for(int i = 0; i < c.getCount();i++){   
            if(c.getString(iExpense) == "House"){
            Result[i] = Integer.parseInt(c.getString(iAmount));
            }
        }
        return Result;
    }

我不确定我错过了什么，谢谢！

Answer 1

您正在将字符串与==进行比较，这是不正确的。使用equals：

  if(c.getString(iExpense).equals("House")) 
    .
    .
    .

Answer 2

public void onCreate(SQLiteDatabase db) {
            // TODO Auto-generated method stub
            db.execSQL("create table " + IncomeTable + " (" + colID + " Integer PRIMARY KEY AUTOINCREMENT, " + colIncome + " money);");
            db.execSQL("create table " +  ExpenseTable + " (" + colExpID + " Integer PRIMARY KEY AUTOINCREMENT, " + colExpExpense + " text, " + colExpAmount + " money);");

        }