Random () Insert data duplication problem

Today, when you write a small test case, you want to insert some data into the database. The random function was used to make the data, and the problem was not noticed before, and it was noticed that the "random number generation repetition problem" did not notice the duplication of the data being inserted.

 for (int010000; i++) {    new  Random ();    Console.WriteLine (RO. Next (+)); }

Verify that, as expected, "if the generated time is very short, then there is a good chance that the generated random number repeats." "and make a record.

Random () Insert data duplication problem