zeroDateTimeBehavior=convertToNull&useUnicode=true&characterEncoding=utf-8
后面这些参数先去掉试试

我用logstash-7.13.4版本可以，配置如下

input {
  jdbc {
    jdbc_driver_library => "E:\elk\logstash-7.13.4\lib\DmJdbcDriver18.jar"
    jdbc_driver_class => "Java::dm.jdbc.driver.DmDriver"
    jdbc_connection_string => "jdbc:dm://192.168.1.11:5236"
    jdbc_user => "SYSDBA"
    jdbc_password => "SYSDBA123"
    schedule => "* * * * *"
    statement => "select user_name,clnt_ip,clnt_ver from v$sessions"
  }
}

注意jdbc_driver_class值的设置，加上Java::