将Mysql中 test表同步到ES中，并且将tags(逗号分隔的字符串)转化数组同步到ES中的数组。
Mysql中test表结构

CREATE TABLE `test` (
    `id` int(10) UNSIGNED NOT NULL AUTO_INCREMENT,
    `name` varchar(100) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL,
    `tags` varchar(1000) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT '',
    PRIMARY KEY (`id`)
) ENGINE=InnoDB
DEFAULT CHARACTER SET=utf8mb4 COLLATE=utf8mb4_general_ci

数据如下：

image.png

ES中数据结构

PUT info-flow-test3
{
  "mappings": {
    "properties": {
      "id": {
        "type": "keyword"
      },
      "tags": {
        "type": "keyword"
      }
    }
  }
}

Flink 中

CREATE TABLE es_info_flow_test3 (
    id string,
    tags ARRAY < string >,
    PRIMARY KEY (id) NOT ENFORCED -- 主键可选，如果定义了主键，则作为文档ID，否则文档ID将为随机值。
  )
WITH (
    'connector' = 'elasticsearch-7',
    'hosts' = '127.0.0.1:9200',
    'index' = 'info-flow-test3',
    'username' = 'elastic',
    'password' = '123456'
  );

CREATE TABLE mysqlcdc_test (
    id INT, tags string, PRIMARY KEY (id) NOT ENFORCED
  )
WITH (
    'connector' = 'mysql-cdc',
    'hostname' = '127.0.0.1',
    'port' = '3306',
    'username' = 'admin',
    'password' = '123456',
    'database-name' = 'test_db',
    'table-name' = 'test'
  );

运行Flink任务脚本如下：

insert into es_info_flow_test3 (id, tags)
select CAST(t.id as STRING) as id, t
from
  mysqlcdc_test t, lateral table (ASI_UDTF (`tags`)) as T (t)

自定义UDTF函数参考阿里云链接，注意需要使用java8
https://help.aliyun.com/document_detail/188055.html
上传jar包后，如果返回如下表明包可以上传。

image.png

查看tags的类型

POST info-flow-test3/_search
返回值：
{
  "took" : 0,
  "timed_out" : false,
    "max_score" : 1.0,
    "hits" : [
      {
        "_index" : "info-flow-test3",
        "_type" : "_doc",
        "_id" : "2",
        "_score" : 1.0,
        "_source" : {
          "id" : "2",
          "tags" : [
            "3",
            "4",
            "5"
          ]
        }
      },
      {
        "_index" : "info-flow-test3",
        "_type" : "_doc",
        "_id" : "3",
        "_score" : 1.0,
        "_source" : {
          "id" : "3",
          "tags" : [
            "6"
          ]
        }
      }
    ]
  }
}