下面sql语句一直提示i和j是无效的，请问这么写哪错了

下面sql语句一直提示i和j是无效的，请问这么写哪错了

"select state from [StockState] where row = " + i + " and [column] = " + j
同学，i和j是变量，你写到sql语句的字符串里，当然是无效的咯

for (int i = 0; i < 3; i++) { for (int j = 0; j < 3; j++) { string sql2 = "select state from [StockState] where row = '"+i+"' and [column] = '"+j+"'"; dt2 = DataBaseHelper.GetDataSet(sql2).Tables[0]; } }