一、深入理解Flink Oracle CDC Connector

Flink CDC系列之：Oracle CDC Connector

二、创建docker-compose.yml文件

version: '2.1'
services:oracle:image: yuxialuo/oracle-xe-11g-r2-cdc-demo:v1.0ports:- "1521:1521"elasticsearch:image: elastic/elasticsearch:7.6.0environment:- cluster.name=docker-cluster- bootstrap.memory_lock=true- "ES_JAVA_OPTS=-Xms512m -Xmx512m"- discovery.type=single-nodeports:- "9200:9200"- "9300:9300"ulimits:memlock:soft: -1hard: -1nofile:soft: 65536hard: 65536kibana:image: elastic/kibana:7.6.0ports:- "5601:5601"volumes:- /var/run/docker.sock:/var/run/docker.sock

该 Docker Compose 中包含的容器有:

Oracle: Oracle 11g, 已经预先创建了 products 和 orders表，并插入了一些数据
Elasticsearch: orders 表将和 products 表进行join，join的结果写入Elasticsearch中
Kibana: 可视化 Elasticsearch 中的数据

三、启动容器

在 docker-compose.yml 所在目录下运行如下命令以启动所有容器：

docker-compose up -d

该命令会以 detached 模式自动启动 Docker Compose 配置中定义的所有容器。你可以通过 docker ps 来观察上述的容器是否正常启动了。也可以访问 http://localhost:5601/ 来查看 Kibana 是否运行正常。另外可以通过如下命令停止所有的容器：

docker-compose down

四、下载Flink Oracle CDC的jar包

下载以下 jar 包到 <FLINK_HOME>/lib/:

flink-sql-connector-elasticsearch7-3.0.1-1.17.jar
flink-sql-connector-oracle-cdc-2.4.1.jar

五、启动 Flink 集群，再启动 SQL CLI

-- Flink SQL
-- checkpoint every 3000 milliseconds                       
Flink SQL> SET execution.checkpointing.interval = 3s;Flink SQL> CREATE TABLE products (ID INT,NAME STRING,DESCRIPTION STRING,PRIMARY KEY (ID) NOT ENFORCED) WITH ('connector' = 'oracle-cdc','hostname' = 'localhost','port' = '1521','username' = 'flinkuser','password' = 'flinkpw','database-name' = 'XE','schema-name' = 'flinkuser',  'table-name' = 'products');Flink SQL> CREATE TABLE orders (ORDER_ID INT,ORDER_DATE TIMESTAMP_LTZ(3),CUSTOMER_NAME STRING,PRICE DECIMAL(10, 5),PRODUCT_ID INT,ORDER_STATUS BOOLEAN) WITH ('connector' = 'oracle-cdc','hostname' = 'localhost','port' = '1521','username' = 'flinkuser','password' = 'flinkpw','database-name' = 'XE','schema-name' = 'flinkuser',  'table-name' = 'orders');

创建elasticsearch

Flink SQL> CREATE TABLE enriched_orders (ORDER_ID INT,ORDER_DATE TIMESTAMP_LTZ(3),CUSTOMER_NAME STRING,PRICE DECIMAL(10, 5),PRODUCT_ID INT,ORDER_STATUS BOOLEAN,PRODUCT_NAME STRING,PRODUCT_DESCRIPTION STRING,PRIMARY KEY (ORDER_ID) NOT ENFORCED) WITH ('connector' = 'elasticsearch-7','hosts' = 'http://localhost:9200','index' = 'enriched_orders_1'

关联处理后，插入数据

Flink SQL> INSERT INTO enriched_ordersSELECT o.*, p.NAME, p.DESCRIPTIONFROM orders AS oLEFT JOIN products AS p ON o.PRODUCT_ID = p.ID;

六、检查 ElasticSearch 中的结果

检查最终的结果是否写入ElasticSearch中, 可以在Kibana看到ElasticSearch中的数据

七、在 Oracle 制造一些变更，观察 ElasticSearch 中的结果

进入Oracle容器中并通过如下的SQL语句对Oracle数据库进行一些修改, 然后就可以看到每执行一条SQL语句，Elasticsearch中的数据都会实时更新。

docker-compose exec sqlplus flinkuser/flinkpw

插入更新数据

INSERT INTO flinkuser.orders VALUES (10004, to_date('2020-07-30 15:22:00', 'yyyy-mm-dd hh24:mi:ss'), 'Jark', 29.71, 104, 0);UPDATE flinkuser.orders SET ORDER_STATUS = 1 WHERE ORDER_ID = 10004;DELETE FROM flinkuser.orders WHERE ORDER_ID = 10004;