presto java

标签：url   连接   select   for   ati   name   imp   group   set   

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class Presto {
  public static void main(String[] args) {
    try {
      long start,end;
      start = System.currentTimeMillis();
      Connection connection = DriverManager.getConnection("jdbc:presto://连接ip:端口/reports/reports?user=admin");
      Statement stmt = connection.createStatement();
      String sql;
      sql="WITH t3 AS (select 字段1,字段2 from 数据表名 group by 字段1,字段2),t4 AS (select url, array_agg(json_extract(json_parse(trim(record)), ‘$.id‘)) as guiderIds,date_trunc(‘day‘,time) as time from 数据表名 group by url,date_trunc(‘day‘,time)) SELECT t4.字段1,t4.字段2,t4.time,t3.字段1 FROM t4 LEFT JOIN t3 ON t4.字段1=t3.字段1";
      System.out.println(sql);
      end = System.currentTimeMillis();
      System.out.print("connect:");
      System.out.println((end - start)/1000);
      for(int i = 0; i < 6; ++i) {//分别执行6次
        start = System.currentTimeMillis();
        ResultSet rs = stmt.executeQuery(sql);
        //System.out.println(rs.getClass().getName().toString());
        end = System.currentTimeMillis();
        System.out.print(i);
        System.out.print(" execute(ms):");
        System.out.print(end - start);
        start = System.currentTimeMillis();
        while (rs.next()) {
          //System.out.println(rs.getString(1));
        }
        rs.close();
        System.out.print(" readData(ms):");
        end = System.currentTimeMillis();
        System.out.println(end - start);
      }
      connection.close();
    }catch(Exception e){
      System.out.println(e);
    }
  }
}

presto java

标签：url   连接   select   for   ati   name   imp   group   set   

原文地址：https://blog.51cto.com/hjun169/2509458