# How can i delete all data stored like flow.set("xy",value)

**URL:** <https://discourse.nodered.org/t/how-can-i-delete-all-data-stored-like-flow-set-xy-value/3864>\
**Category:** General\
**Created:** [10 October 2018 16:40 UTC](https://discourse.nodered.org/t/how-can-i-delete-all-data-stored-like-flow-set-xy-value/3864 "2018-10-10T16:40:18Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![MarkusR](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/markusr/32/2934_2.png) [@MarkusR](https://discourse.nodered.org/u/MarkusR)\
**Post date:** [10 October 2018 16:40 UTC](https://discourse.nodered.org/t/how-can-i-delete-all-data-stored-like-flow-set-xy-value/3864/1 "2018-10-10T16:40:18Z")

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hello,  
i collect data by mqtt topic.  
so i count something in flow.set(msg.topic,flow.get(msg.topic)+1)  
this data i push into a chart.  
**but how can i remove all in flow. ?**  
i will reset the data stored in flow. each day with the rbe node that it will count from 0.

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**Author:** ![ukmoose](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ukmoose/32/13_2.png) [@ukmoose](https://discourse.nodered.org/u/ukmoose)\
**Post date:** [10 October 2018 17:45 UTC](https://discourse.nodered.org/t/how-can-i-delete-all-data-stored-like-flow-set-xy-value/3864/2 "2018-10-10T17:45:11Z")

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just use flow set to set it to null or 0

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<div class="post-metadata">

**Author:** ![MarkusR](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/markusr/32/2934_2.png) [@MarkusR](https://discourse.nodered.org/u/MarkusR)\
**Post date:** [10 October 2018 17:58 UTC](https://discourse.nodered.org/t/how-can-i-delete-all-data-stored-like-flow-set-xy-value/3864/3 "2018-10-10T17:58:49Z")

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my problem is i have multiple keys, i will remove all key,value pairs.

i found this solution but the keys are still there.

i missing flow.clear()

> var keys = flow.keys();  
> for (index = 0; index \< keys.length; ++index) {  
> flow.set(keys[index],null);  
> }

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<div class="post-metadata">

**Author:** ![hotNipi](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/hotnipi/32/383_2.png) [@hotNipi](https://discourse.nodered.org/u/hotNipi)\
**Post date:** [10 October 2018 18:08 UTC](https://discourse.nodered.org/t/how-can-i-delete-all-data-stored-like-flow-set-xy-value/3864/4 "2018-10-10T18:08:14Z")

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`flow.set(keys[index]);`

😉

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<div class="post-metadata">

**Author:** ![ukmoose](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ukmoose/32/13_2.png) [@ukmoose](https://discourse.nodered.org/u/ukmoose)\
**Post date:** [10 October 2018 18:11 UTC](https://discourse.nodered.org/t/how-can-i-delete-all-data-stored-like-flow-set-xy-value/3864/5 "2018-10-10T18:11:33Z")

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or you should be able to delete it totally with a change node set to delete

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<div class="post-metadata">

**Author:** ![MarkusR](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/markusr/32/2934_2.png) [@MarkusR](https://discourse.nodered.org/u/MarkusR)\
**Post date:** [10 October 2018 21:09 UTC](https://discourse.nodered.org/t/how-can-i-delete-all-data-stored-like-flow-set-xy-value/3864/6 "2018-10-10T21:09:39Z")

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thanks, this syntax seems to remove it.