# Update all fields containing specific string in field name by painless script
**URL:** https://discuss.elastic.co/t/update-all-fields-containing-specific-string-in-field-name-by-painless-script/275973
**Category:** Elasticsearch
**Tags:** painless
**Created:** [June 15, 2021, 9:55am UTC](https://discuss.elastic.co/t/update-all-fields-containing-specific-string-in-field-name-by-painless-script/275973 "2021-06-15T09:55:06Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@sbienert](https://discuss.elastic.co/u/sbienert)
#### Post date: [June 15, 2021, 9:55am UTC](https://discuss.elastic.co/t/update-all-fields-containing-specific-string-in-field-name-by-painless-script/275973/1 "2021-06-15T09:55:06Z")
Hi, I have a pretty simple request but I don't manage to get it working. I need to increase a datetime of multiple fields in one document. The date fields can be nested fields at different levels. Instead of having to update every single field specifically I wanted to update all fields containing "Date" in the field name. I tried it like this (with \_update\_by\_query):
```auto
{
"script": {
"source": "def df = DateTimeFormatter.ISO_OFFSET_DATE_TIME; Iterator it = ctx.entrySet().iterator(); while (it.hasNext()) { if (it.next().getKey().contains(\"Date\") && it.next().getValue() != null) { def tmp = OffsetDateTime.parse(it.next().getValue(),df); it.next().getValue()=tmp.plusDays(1);}}",
"lang": "painless"
}
}
```
But it does not work (giving error message "Left-hand side cannot be assigned a value."). Can anyone tell me how it could work or if it even yould work?
Thanks in advance
---
### Author:  [@system](https://discuss.elastic.co/u/system)
#### Post date: [July 13, 2021, 9:55am UTC](https://discuss.elastic.co/t/update-all-fields-containing-specific-string-in-field-name-by-painless-script/275973/2 "2021-07-13T09:55:13Z")
This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.