Logstash to Elasticsearch - data update

[katara]

I am trying to update an existing data in my Elasticsearch Index. Im using the below Logstash configuration:

input {
    jdbc {
        jdbc_connection_string => "jdbc:sqlserver://DB01:1433;databasename=mydb;integratedSecurity=true"
        jdbc_driver_class =>  "com.microsoft.sqlserver.jdbc.SQLServerDriver"
    jdbc_driver_library => "C:\Program Files\sqljdbc_6.2\enu\mssql-jdbc-6.2.2.jre8.jar"
        jdbc_user => nil
        statement => "SELECT * from data WHERE updated_on > :sql_last_value ORDER BY updated_on"
    use_column_value =>true
        tracking_column =>updated_on
        tracking_column_type => "timestamp"
    }
}
output {
          elasticsearch { hosts => ["localhost:9200"] 
        index => "datau" 
        action=>update
            document_id => "%{id}"
            doc_as_upsert =>true}
          stdout { codec => rubydebug }
       }

When i run this, any updation on the existing row is created as a new row. I want to to get updated in the existing row.

How do i do it? Please help me.