# Painless is not that painless
**URL:** https://discuss.elastic.co/t/painless-is-not-that-painless/263982
**Category:** Kibana
**Tags:** painless
**Created:** [February 11, 2021, 10:06am UTC](https://discuss.elastic.co/t/painless-is-not-that-painless/263982 "2021-02-11T10:06:22Z")
**Posts on this page:** 8
**Page:** 1
### Author:  [@Casper\_Thrane](https://discuss.elastic.co/u/Casper_Thrane)
#### Post date: [February 11, 2021, 10:06am UTC](https://discuss.elastic.co/t/painless-is-not-that-painless/263982/1 "2021-02-11T10:06:22Z")
Hi
I am a simple thing, like assigning a text to a string variable, and then just return the value. But I keep getting compile error:
```
if (!doc.containsKey("url.query") || doc["url.query"].empty) {
return null;
}
String params = "hej";
return params;
```
The compiler error is with the String type? What am i doing wrong. I think the painless very often, can painfull instead.
/Casper
---
### Author:  [@aaron-nimocks](https://discuss.elastic.co/u/aaron-nimocks)
#### Post date: [February 11, 2021, 12:42pm UTC](https://discuss.elastic.co/t/painless-is-not-that-painless/263982/2 "2021-02-11T12:42:59Z")
Where are you doing this script?
What is the mapping of the field you are trying to run a script against?
I am assuming you are doing a script against a field that isn't a `String`.
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### Author:  [@Casper\_Thrane](https://discuss.elastic.co/u/Casper_Thrane)
#### Post date: [February 11, 2021, 8:45pm UTC](https://discuss.elastic.co/t/painless-is-not-that-painless/263982/3 "2021-02-11T20:45:13Z")
I was creating a scripted field in Kibana. I solved the problem by changing the variable name from params to tmp??? I didn't know params is reserved word.
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### Author:  [@aaron-nimocks](https://discuss.elastic.co/u/aaron-nimocks)
#### Post date: [February 11, 2021, 8:57pm UTC](https://discuss.elastic.co/t/painless-is-not-that-painless/263982/4 "2021-02-11T20:57:17Z")
I know it's reserved in Painless Lab but wouldn't think it carries over from that. Guess it's also used in templates and queries, passing in `params`.
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### Author:  [@system](https://discuss.elastic.co/u/system)
#### Post date: [March 11, 2021, 8:57pm UTC](https://discuss.elastic.co/t/painless-is-not-that-painless/263982/5 "2021-03-11T20:57:21Z")
This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.
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### Author:  [@AdamWritesDocs](https://discuss.elastic.co/u/AdamWritesDocs)
#### Post date: [May 4, 2021, 3:44pm UTC](https://discuss.elastic.co/t/painless-is-not-that-painless/263982/6 "2021-05-04T15:44:55Z")
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### Author:  [@AdamWritesDocs](https://discuss.elastic.co/u/AdamWritesDocs)
#### Post date: [May 4, 2021, 3:47pm UTC](https://discuss.elastic.co/t/painless-is-not-that-painless/263982/7 "2021-05-04T15:47:02Z")
@Casper_Thrane, we recently updated our documentation for [how to write scripts](https://www.elastic.co/guide/en/elasticsearch/reference/current/modules-scripting-using.html). Hopefully this information helps, but if not, please let us know where we can improve!
Also, consider using [runtime fields](https://www.elastic.co/guide/en/elasticsearch/reference/current/runtime.html) instead of Kibana scripted fields. They're more flexible, and you don't need to index them.
---
### Author:  [@system](https://discuss.elastic.co/u/system)
#### Post date: [November 4, 2022, 8:23am UTC](https://discuss.elastic.co/t/painless-is-not-that-painless/263982/9 "2022-11-04T08:23:55Z")