1. 导言:
Apache Flink是一款功能强大的流式处理引擎,可用于实时处理大规模数据。本文将介绍如何使用Flink与MySQL数据库进行交互,以清洗股票数据为例。
2. 环境准备:
首先,确保已安装Apache Flink并配置好MySQL数据库。导入相关依赖包,并创建必要的Table。同时需要提前创建好mysql表,一行source表,一张sink表。
CREATE TABLE `re_stock_code_price` (`id` bigint NOT NULL AUTO_INCREMENT,`code` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '股票代码',`name` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '股票名称',`close` double DEFAULT NULL COMMENT '最新价',`change_percent` double DEFAULT NULL COMMENT '涨跌幅',`change` double DEFAULT NULL COMMENT '涨跌额',`volume` double DEFAULT NULL COMMENT '成交量(手)',`amount` double DEFAULT NULL COMMENT '成交额',`amplitude` double DEFAULT NULL COMMENT '振幅',`turnover_rate` double DEFAULT NULL COMMENT '换手率',`peration` double DEFAULT NULL COMMENT '市盈率',`volume_rate` double DEFAULT NULL COMMENT '量比',`hign` double DEFAULT NULL COMMENT '最高',`low` double DEFAULT NULL COMMENT '最低',`open` double DEFAULT NULL COMMENT '今开',`previous_close` double DEFAULT NULL COMMENT '昨收',`pb` double DEFAULT NULL COMMENT '市净率',`create_time` varchar(64) NOT NULL COMMENT '写入时间',`rise` int NOT NULL,PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=11207 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci CREATE TABLE `t_stock_code_price` (`id` bigint NOT NULL AUTO_INCREMENT,`code` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '股票代码',`name` varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '股票名称',`close` double DEFAULT NULL COMMENT '最新价',`change_percent` double DEFAULT NULL COMMENT '涨跌幅',`change` double DEFAULT NULL COMMENT '涨跌额',`volume` double DEFAULT NULL COMMENT '成交量(手)',`amount` double DEFAULT NULL COMMENT '成交额',`amplitude` double DEFAULT NULL COMMENT '振幅',`turnover_rate` double DEFAULT NULL COMMENT '换手率',`peration` double DEFAULT NULL COMMENT '市盈率',`volume_rate` double DEFAULT NULL COMMENT '量比',`hign` double DEFAULT NULL COMMENT '最高',`low` double DEFAULT NULL COMMENT '最低',`open` double DEFAULT NULL COMMENT '今开',`previous_close` double DEFAULT NULL COMMENT '昨收',`pb` double DEFAULT NULL COMMENT '市净率',`create_time` varchar(64) NOT NULL COMMENT '写入时间',PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=11207 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
package org.east;import org.apache.flink.api.common.RuntimeExecutionMode;
import org.apache.flink.streaming.api.scala.StreamExecutionEnvironment;
import org.apache.flink.table.api.bridge.scala.StreamTableEnvironment;object TableETL {def main(args: Array[String]): Unit = {val senv = StreamExecutionEnvironment.getExecutionEnvironment.setRuntimeMode(RuntimeExecutionMode.STREAMING)val tEnv = StreamTableEnvironment.create(senv)// 定义源表val source_table ="""CREATE TEMPORARY TABLE t_stock_code_price (id BIGINT NOT NULL,code STRING NOT NULL,-- 其他字段...create_time STRING NOT NULL,PRIMARY KEY (id) NOT ENFORCED) WITH ('connector' = 'jdbc','url' = 'jdbc:mysql://localhost:3306/mydb','driver' = 'com.mysql.cj.jdbc.Driver','table-name' = 't_stock_code_price','username' = 'root','password' = '12345678')""".stripMargin// 定义目标表val sink_table ="""CREATE TEMPORARY TABLE re_stock_code_price (id BIGINT NOT NULL,code STRING NOT NULL,-- 其他字段...create_time STRING NOT NULL,rise INT,PRIMARY KEY (id) NOT ENFORCED) WITH ('connector' = 'jdbc','url' = 'jdbc:mysql://localhost:3306/mydb','driver' = 'com.mysql.cj.jdbc.Driver','table-name' = 're_stock_code_price','username' = 'root','password' = '12345678')""".stripMargintEnv.executeSql(source_table)tEnv.executeSql(sink_table)
在这段代码中,我们首先创建了Flink的流式执行环境和StreamTableEnvironment。然后,我们定义了两个临时表,用于存储原始股票数据和清洗后的数据。
3. 数据清洗:
接下来,我们执行数据清洗操作,并将结果写入目标表。
// 执行清洗操作,并将结果写入目标表tEnv.executeSql("INSERT INTO re_stock_code_price " +"SELECT *, CASE WHEN change_percent > 0 THEN 1 ELSE 0 END AS rise FROM t_stock_code_price")
在这里,我们计算了股票涨跌情况,并将结果写入到目标表中。在这个例子中,我们假设change_percent字段表示股票价格的变化百分比,rise字段为1表示股票上涨,为0表示股票下跌。
4. 结果展示:
最后,我们查询目标表并打印结果。
5. 完整代码:
下面是完整的代码:
package org.east;
import org.apache.flink.api.common.RuntimeExecutionMode
import org.apache.flink.streaming.api.scala.StreamExecutionEnvironment
import org.apache.flink.table.api.bridge.scala.StreamTableEnvironmentobject TableETL {def main(args: Array[String]): Unit = {val senv = StreamExecutionEnvironment.getExecutionEnvironment.setRuntimeMode(RuntimeExecutionMode.STREAMING)val tEnv = StreamTableEnvironment.create(senv)val source_table ="""|CREATE TEMPORARY TABLE t_stock_code_price (| id BIGINT NOT NULL,| code STRING NOT NULL,| name STRING NOT NULL,| `close` DOUBLE,| change_percent DOUBLE,| change DOUBLE,| volume DOUBLE,| amount DOUBLE,| amplitude DOUBLE,| turnover_rate DOUBLE,| peration DOUBLE,| volume_rate DOUBLE,| hign DOUBLE,| low DOUBLE,| `open` DOUBLE,| previous_close DOUBLE,| pb DOUBLE,| create_time STRING NOT NULL,| PRIMARY KEY (id) NOT ENFORCED|) WITH (| 'connector' = 'jdbc',| 'url' = 'jdbc:mysql://localhost:3306/mydb',| 'driver' = 'com.mysql.cj.jdbc.Driver',| 'table-name' = 't_stock_code_price',| 'username' = 'root',| 'password' = '12345678'|)|""".stripMarginval sink_table ="""|CREATE TEMPORARY TABLE re_stock_code_price (| id BIGINT NOT NULL,| code STRING NOT NULL,| name STRING NOT NULL,| `close` DOUBLE,| change_percent DOUBLE,| change DOUBLE,| volume DOUBLE,| amount DOUBLE,| amplitude DOUBLE,| turnover_rate DOUBLE,| peration DOUBLE,| volume_rate DOUBLE,| hign DOUBLE,| low DOUBLE,| `open` DOUBLE,| previous_close DOUBLE,| pb DOUBLE,| create_time STRING NOT NULL,| rise int,| PRIMARY KEY (id) NOT ENFORCED|) WITH (| 'connector' = 'jdbc',| 'url' = 'jdbc:mysql://localhost:3306/mydb',| 'driver' = 'com.mysql.cj.jdbc.Driver',| 'table-name' = 're_stock_code_price',| 'username' = 'root',| 'password' = '12345678'|)|""".stripMargintEnv.executeSql(source_table)tEnv.executeSql(sink_table)tEnv.executeSql("insert into re_stock_code_price select *,case when change_percent>0 then 1 else 0 end as rise from t_stock_code_price")val user_DS = tEnv.executeSql("select * from re_stock_code_price")user_DS.print()}
}
如有遇到问题可以找小编沟通交流哦。另外小编帮忙辅导大课作业,学生毕设等。不限于python,java,大数据,模型训练等。