jdbc - java.sql.SQLException:<field_name>的验证失败: 'null'无法强制转换为double类型

Question

我正在使用logstash创建从elasticsearch到crate.io的管道。下面是配置。

input{
 elasticsearch {
   hosts => "<host_name>:9200"
   index => "index1"
   query => '{ "size":10,"query": {"match_all": {} } }'
   }
}
filter{
    if!([bench_pose][M_Body_t]) {
            mutate{
                    add_field => {"[bench_pose][M_Body_t]" => null}
            }
    }
    if!([bench_pose][M_Jaw_t]) {
            mutate{
                    add_field => {"[bench_pose][M_Jaw_t]" => null}
            }
    }
}
output{
 jdbc {
       driver_class => "io.crate.client.jdbc.CrateDriver"
       driver_auto_commit => false
       driver_jar_path => "/etc/crate/crate-jdbc-standalone-1.12.3.jar"
       connection_string => "crate://<host_ip>:4300"
       statement => ["INSERT INTO table_name(path,bench_pose_m_Body_t,bench_pose_m_jaw_t) VALUES(?,?,?)",'path','%{[bench_pose][M_Body_t]}','%{[bench_pose][M_Jaw_t]}']
   }
}

源具有字段OBJECT数据类型的“bench_pose”字段，并且Bench_pose下的M_Body_t和M_Jaw_t字段为DOUBLE类型。这些字段在源和目标中可以为NULL。在源中的少数文档中，该字段具有空值。即使目标表具有NULLable字段，当insert语句遇到具有空值的文档时，也会引发以下错误。

JDBC - Exception. Not retrying. {:exception=>java.sql.SQLException: Validation failed for bench_pose_m_body_t: 'null' cannot be cast to type double  

如果删除过滤器插件，则会引发如下错误。

JDBC - Exception. Not retrying. {:exception=>java.sql.SQLException: Validation failed for bench_pose_m_body_t: '%{[bench_pose][M_Body_t]}' cannot be cast to type double

如果我在插入中硬编码null值并在crate sql上运行查询，它将正确执行。
如何在Logstash中解析这些字段中的空值？

Answer 1

您需要将INSERT语句更改为此:

   statement => ["INSERT INTO table_name(path,benc‌​h_pose_m_Body_t,bench‌​_pose_m_jaw_t) VALUES(?,TRY_CAST(? as double),TRY_CAST(? as double))",'path','%{[bench_pose][M_Body_t]}','%{[bench_pose][M_Jaw_t]}']

如果类型转换不兼容， TRY_CAST 将返回null而不是抛出错误。