============问题描述============
============解决方案1============
int sum(SQLiteDatabase db) {
Cursor cursor = db.rawQuery("select sum(e) from a", null);
cursor.moveToNext();
int sum = cursor.getInt(0);
cursor.close();
return sum;
}
============解决方案2============
int sum() {
SQLiteDatabase db = dbManger.getInstance();
Cursor cursor = db.rawQuery("select sum(e) from a", null);
cursor.moveToNext();
int sum = cursor.getInt(0);
cursor.close();
db.close();
return sum;
}
原文:http://www.cnblogs.com/hugangyan86/p/4041969.html