# How to check duplicate value

**URL:** <https://discourse.nodered.org/t/how-to-check-duplicate-value/75977>\
**Category:** General\
**Tags:** node-red-dashboard\
**Created:** [2 March 2023 06:23 UTC](https://discourse.nodered.org/t/how-to-check-duplicate-value/75977 "2023-03-02T06:23:54Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![komkitPP](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/komkitpp/32/76273_2.png) [@komkitPP](https://discourse.nodered.org/u/komkitPP)\
**Post date:** [2 March 2023 06:23 UTC](https://discourse.nodered.org/t/how-to-check-duplicate-value/75977/1 "2023-03-02T06:23:54Z")

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Example : If the value is 6, not insert value 6 again.

I use switch

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/5/b/5b41d0848cf8ac69ce04f4fea509d74766357f2e.png)  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/b/d/bd5cb7f4ad4dbe9783665d33f1e0d965ba8ba20e.png)  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/9/5/9553105fec6121a0eb2f2f294336f49c5b9f3b8e.png)

**\> `**  **> How to check**  **> `**

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**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [2 March 2023 07:43 UTC](https://discourse.nodered.org/t/how-to-check-duplicate-value/75977/2 "2023-03-02T07:43:07Z")

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That switch node is redundant - you are comparing the same value to itself. It will always be true.

Try deleting the switch node and replacing it with an RBE node.

The RBE node is also called the FILTER node - you can find it in the pallet on the left hand side.

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**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [1 May 2023 07:43 UTC](https://discourse.nodered.org/t/how-to-check-duplicate-value/75977/3 "2023-05-01T07:43:30Z")

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