CRUD Operations In Postgres Using C#

public string ConnectionString {
  get {
    return@"Provider=PostgreSQL OLE DB Provider;Server=127.0.0.1;
Database=<db_name>;User ID=<user_name>;password=<password>;";
  }
}

public DataTable GetResultSetTable(string query) {
  DataTable table = new DataTable();
  using(NpgsqlConnection connection = new NpgsqlConnection(ConnectionString)) {
    connection.Open();
    using(NpgsqlCommand command = new NpgsqlCommand(query, connection)) {
      using(NpgsqlDataAdapter adapter = new NpgsqlDataAdapter()) {
        adapter.SelectCommand = command;
        adapter.Fill(table);
      }
    }
  }
  return table;
}

public void ExecuteQuery(string query) {
  using(NpgsqlConnection connection = new NpgsqlConnection(ConnectionString)) {
    connection.Open();
    using(NpgsqlCommand command = new NpgsqlCommand(query, connection)) {
      command.ExecuteNonQuery();
    }
  }
}

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