分库数据怎么查询统计

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public Connection   getConnection(String drivername,String url, String username, String passWord)   {

                  try   {

                                    Class.forName(drivername);

                                    conn   = DriverManager.getConnection(url, username, password);

                  }   catch (Exception e) {

                                    System.out.println("DBUtils.getConnection_FaiLED!");

                                    e.printStackTrace();

                  }

                  return   conn;

}

…

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Connection conn1 = DBUtils.getConnection(URL1,   USER1, PASSWORD1);

Connection conn2 = DBUtils.getConnection(URL2,   USER2, PASSWORD2);

…

String sql = "select count(*) c from   sales";

PreparedStatement ptmt1 = conn1.prepareStatement(sql);

PreparedStatement ptmt2 = conn1.prepareStatement(sql);

…

ResultSet rs1 = ptmt1.executeQuery();

ResultSet rs2 = ptmt2.executeQuery();

…

return rs1.getInt("c")   + rs2.getInt("c");

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