Select 获取字段时的查询问题

Question

我写了一个查询，其中 select 基于 id 的名称和指定字段，然后在片段 class 我正在调用属于适当查询的方法，但不幸的是我得到了 Sqlite 异常.

数据库方法

public Employee getEmployeeName(int id) {
    SQLiteDatabase db = this.getWritableDatabase();
    Employee employee = new Employee();
    String query ="SELECT  " + KEY_NAME +", " +KEY_DESIG +" FROM " + TABLE_EMPLOYEES+ " WHERE " + KEY_ID + "=" + id;
    Cursor cursor = db.rawQuery(query, null);
    if (cursor.moveToFirst()) {
        do {
            employee.setName(cursor.getString(1));
            employee.setDesignation(cursor.getString(2));
        } while (cursor.moveToNext());
    }
    return employee;

}

从片段调用

db.getEmployeeName(selectedManager);

异常

01-07 06:02:34.185: E/AndroidRuntime(2386): java.lang.IllegalStateException: Couldn't read row 0, col 2 from CursorWindow.  Make sure the Cursor is initialized correctly before accessing data from it.

Answer 1

试试这个

 if (cursor.moveToFirst()) {
    do {
        employee.setName(cursor.getString(cursor.getColumnIndex(KEY_NAME));
        employee.setDesignation(cursor.getString(cursor.getColumnIndex(KEY_DESIG));
    } while (cursor.moveToNext());
}

使用 cursor.getColumnIndex(COLUMN NAME)

从 Cursor 获取数据

Answer 2

列索引是从零开始的。 getString(2)指的是第三列，而您的光标只有两列。

改变

employee.setName(cursor.getString(1));
employee.setDesignation(cursor.getString(2));

至

employee.setName(cursor.getString(0));
employee.setDesignation(cursor.getString(1));

Select 获取字段时的查询问题

Select Query issue while fetching the fields

sqlite

android