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anypoint studio - How to throw an error message if id field exist in POST request in Mulesoft 4 - Stack Overflow
![Session 2 : Dataweave 2.0 | subString | subStringBefore | subStringAfter Functions | Mule 4 - YouTube Session 2 : Dataweave 2.0 | subString | subStringBefore | subStringAfter Functions | Mule 4 - YouTube](https://i.ytimg.com/vi/WtCzpFB_5zk/maxresdefault.jpg)
Session 2 : Dataweave 2.0 | subString | subStringBefore | subStringAfter Functions | Mule 4 - YouTube
![Session 2 : Dataweave 2.0 | subString | subStringBefore | subStringAfter Functions | Mule 4 - YouTube Session 2 : Dataweave 2.0 | subString | subStringBefore | subStringAfter Functions | Mule 4 - YouTube](https://i.ytimg.com/vi/WtCzpFB_5zk/sddefault.jpg)
Session 2 : Dataweave 2.0 | subString | subStringBefore | subStringAfter Functions | Mule 4 - YouTube
![Session 2 : Dataweave 2.0 | subString | subStringBefore | subStringAfter Functions | Mule 4 - YouTube Session 2 : Dataweave 2.0 | subString | subStringBefore | subStringAfter Functions | Mule 4 - YouTube](https://i.ytimg.com/vi/90dMfyPZ4k0/hq720.jpg?sqp=-oaymwEhCK4FEIIDSFryq4qpAxMIARUAAAAAGAElAADIQj0AgKJD&rs=AOn4CLAgVrSaAxb_nKs1dRtXMULdBtc7sw)