# Update by query gives java error
**URL:** https://discuss.elastic.co/t/update-by-query-gives-java-error/62811
**Category:** Elasticsearch
**Created:** [October 12, 2016, 1:54pm UTC](https://discuss.elastic.co/t/update-by-query-gives-java-error/62811 "2016-10-12T13:54:02Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@Mahdy\_S](https://discuss.elastic.co/u/Mahdy_S)
#### Post date: [October 12, 2016, 1:54pm UTC](https://discuss.elastic.co/t/update-by-query-gives-java-error/62811/1 "2016-10-12T13:54:02Z")
Hello,
I am trying to update several documents based on a search query. My use case is to search for documents where two fields match certain values and then add a new field with a certain value. So let's say I want to search all employees with first name "John" and last name "Smith" and add a new field "job" to their profiles with the value "Engineer" in it.
To do this, I am using the update by query API with the "script" option. My code looks like follows:
> curl -XPOST -s '[http://localhost:9200/test\_index/\_update\_by\_query?conflicts=proceed](http://localhost:9200/test_index/_update_by_query?conflicts=proceed)' -d'
> {
> "query": {
> "filtered": {
> "query": {
> "match\_all": {}
> },
> "filter": {
> "bool": {
> "must": [
> {
> "match": { "first\_name" : "John" }
> },
> {
> "match": { "last\_name" : "Smith" }
> }
> ]
> }
> }
> }
> },
> "script" : "ctx.\_source.job = "Engineer""
> }'
Whenever I run this on ubuntu terminal I get the following error:
> {"error":{"root\_cause":[{"type":"class\_cast\_exception","reason":"java.lang.String cannot be cast to java.util.Map"}],"type":"class\_cast\_exception","reason":"java.lang.String cannot be cast to java.util.Map"},"status":500}
However, sending the same query (without the "script" field) using the count API works fine and gives the correct number of documents.
My questions:
- Where is exactly the error in the code I'm using? Unfortunately the error message does not specify in which line the problem is
- Is it possible to use "doc" instead of "script" in the update by query API exactly the same way this is used in Update API?
Elasticsearch version is 2.3.4
---
### Author:  [@acabrol](https://discuss.elastic.co/u/acabrol)
#### Post date: [October 13, 2016, 10:23pm UTC](https://discuss.elastic.co/t/update-by-query-gives-java-error/62811/2 "2016-10-13T22:23:22Z")
I have the same issue with elasticsearch 2.3.4
```
curl -XPOST 'localhost:9200/watch/_update_by_query' -d '{
"query":{ "type" : {"value" : "doc"} },
"script" : "if (ctx._source[\"topics\"] != null) {ctx._source.remove(\"topics\")"}
}'
```
and result:
> {"error":{"root\_cause":[{"type":"class\_cast\_exception","reason":"java.lang.String cannot be cast to java.util.Map"}],"type":"class\_cast\_exception","reason":"java.lang.String cannot be cast to java.util.Map"},"status":500}
topics field is a nested object (if it can help).
---
### Author:  [@Gautam\_Vanani](https://discuss.elastic.co/u/Gautam_Vanani)
#### Post date: [March 30, 2017, 4:22am UTC](https://discuss.elastic.co/t/update-by-query-gives-java-error/62811/3 "2017-03-30T04:22:05Z")
I'm facing same issue while appeding data in array type using script,
> using update\_by\_query:
>
> > POST /srk/demo\_array/\_update\_by\_query
> > {
> > "script" : "ctx.\_source.array += arr",
> > "params" : {
> > "arr" : ["a", "b"]
> > }
> > }
> java error:
>
> > {
> > "error": {
> > "root\_cause": [
> > {
> > "type": "class\_cast\_exception",
> > "reason": "java.lang.String cannot be cast to java.util.Map"
> > }
> > ],
> > "type": "class\_cast\_exception",
> > "reason": "java.lang.String cannot be cast to java.util.Map"
> > },
> > "status": 500
> > }
---
### Author:  [@seanziee](https://discuss.elastic.co/u/seanziee)
#### Post date: [May 26, 2017, 10:05pm UTC](https://discuss.elastic.co/t/update-by-query-gives-java-error/62811/4 "2017-05-26T22:05:34Z")
I had this same problem but figured it out. You need to add "inline" to make it work:
```
POST /logstash-*/_update_by_query
{
"script": {
"inline": "ctx._source.remove(\"ENTERFIELD\")"
},
"query": {
"bool": {
"must": [
{
"exists": {
"field": "ENTERFIELD"
}
}
]
}
}
}
```
---
### Author:  [@system](https://discuss.elastic.co/u/system)
#### Post date: [July 5, 2017, 9:59pm UTC](https://discuss.elastic.co/t/update-by-query-gives-java-error/62811/5 "2017-07-05T21:59:58Z")