spark并行度加载关系数据库

方法一：针对整形字段ECI进行并行度加载：并行度为3

        SparkConf sparkConf = new SparkConf();
        sparkConf.setAppName("jdbc").setMaster("local[4]");
        JavaSparkContext jsc = new JavaSparkContext(sparkConf);
        SQLContext sc = new SQLContext(jsc);
        String url ="jdbc:sqlserver://192.168.1.101;DatabaseName=database;user=user;password=123456";
        String tableName = "tb_city";
        Properties connectionProperties  = new Properties();
        connectionProperties.put("driver", "com.microsoft.sqlserver.jdbc.SQLServerDriver");
        DataFrame table = sc.read().jdbc(url,tableName,"ECI",125883650,263780907,3,connectionProperties).select("CityID","IMSI","ECI");

方法二：针对varchar字段IMSI进行并行度加载：并行度为3

        SparkConf sparkConf = new SparkConf();
        sparkConf.setAppName("jdbc").setMaster("local[4]");
        JavaSparkContext jsc = new JavaSparkContext(sparkConf);
        SQLContext sc = new SQLContext(jsc);
        String url ="jdbc:sqlserver://192.168.1.101;DatabaseName=database;user=user;password=123456";
        String tableName = "tb_city";
        Properties connectionProperties  = new Properties();
        connectionProperties.put("driver", "com.microsoft.sqlserver.jdbc.SQLServerDriver");
        String[] predicates = new String[]{
                "IMSI >='105156335255615' AND IMSI <='145437785776944'",
                "IMSI >='145441560321876' AND IMSI <='145441636521493'",
                "IMSI >'145441636521493' AND IMSI <='145464988025176'",
        };
        DataFrame table = sc.read().jdbc(url,tableName,predicates,connectionProperties).select("CityID","IMSI");

predicates内是筛选条件。三个筛选条件对应三个分区。