# Logstash jdbc plugin - filter issue

**URL:** <https://discuss.elastic.co/t/logstash-jdbc-plugin-filter-issue/37342>\
**Category:** Logstash\
**Created:** [December 16, 2015, 11:04am UTC](https://discuss.elastic.co/t/logstash-jdbc-plugin-filter-issue/37342 "2015-12-16T11:04:05Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![srinivas](https://avatars.discourse-cdn.com/v4/letter/s/ecccb3/32.png) [@srinivas](https://discuss.elastic.co/u/srinivas)\
**Post date:** [December 16, 2015, 11:04am UTC](https://discuss.elastic.co/t/logstash-jdbc-plugin-filter-issue/37342/1 "2015-12-16T11:04:06Z")

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I am using below filter to copy content in COLUMN1 into COLUMN2.  
`filter { mutate { add_field => { "COLUMN2" => "%{COLUMN1 }" } } }`  
But if any value in COLUMN1 is null then its copying the value as %{COLUMN1 } into COLUMN2  
How to avoid it printing %{COLUMN1 } and print null

---

<div class="post-metadata">

**Author:** ![magnusbaeck](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/magnusbaeck/32/44943_2.png) [@magnusbaeck](https://discuss.elastic.co/u/magnusbaeck)\
**Post date:** [December 16, 2015, 11:34am UTC](https://discuss.elastic.co/t/logstash-jdbc-plugin-filter-issue/37342/2 "2015-12-16T11:34:36Z")

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```auto
filter { 
  if [COLUMN1] {
    mutate {
      add_field => {
        "COLUMN2" => "%{COLUMN1}" 
      }
    }
  }
}

```

Caveat: If COLUMN1 exists and is a boolean value that's false the conditional will incorrectly be false.

(This has nothing to do with the JDBC input plugin.)

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [July 6, 2017, 5:18am UTC](https://discuss.elastic.co/t/logstash-jdbc-plugin-filter-issue/37342/3 "2017-07-06T05:18:12Z")

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