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dineshkumarravi
Frequent Visitor

Getting 400 Error while preview the lookup activity

Hi,

I am facing an issue while previewing the lookup activity — it shows a 400 error. However, when I run the procedure alone, it works fine, and another lookup activity is also working. For reference, I have attached a screenshot below.

 

dineshkumarravi_2-1749620948258.png

 

 

dineshkumarravi_0-1749620853137.png

 

9 REPLIES 9
Anushka96
Frequent Visitor

@v-kpoloju-msft  Is there any update with that? 

Anushka96
Frequent Visitor

We're are facing same issue.  Anyone found a solution. I think this is happening from fabric end.

v-kpoloju-msft
Community Support
Community Support

Hi @dineshkumarravi,
Thank you for reaching out to the Microsoft fabric community forum.

When we have reproduced the issue and we are getting timeout error. Could you please let us know the latest error screenshot. is it 400 error or the time out?

Thank you for using the Microsoft Community Forum.

Hi @dineshkumarravi

After thoroughly reviewing the details you provided, I reproduced the scenario again, and it worked on my end. I used it as sample data and successfully implemented it.

This might be an intermittent issue. It is currently working for us. Please let us know if you continue to experience the same problem.


vkpolojumsft_0-1749702182859.png



If this post helps, then please give us ‘Kudos’ and consider Accept it as a solution to help the other members find it more quickly.

Thank you for using Microsoft Community Forum.

Hi @dineshkumarravi,

May I ask if you have resolved this issue? If so, please mark the helpful reply and accept it as the solution. This will be helpful for other community members who have similar problems to solve it faster.

Thank you.

Hi @dineshkumarravi,

I wanted to check if you had the opportunity to review the information provided. Please feel free to contact us if you have any further questions. If my response has addressed your query, please accept it as a solution and give a 'Kudos' so other members can easily find it.
Thank you.

Hi @dineshkumarravi ,

the problem is still there. I think there are three different problems or changes in behavior in the last week, but one serious.
1. If in query is some small syntax error, like a semicolon at the end for Oracle DB, it returns a nonsensical 400 error.
2. If the preview contains two columns of the same name it again returns a nonsense error 400
3. If the query is a more complex query and the preview takes more than approximately 100 seconds, it returns error 408. This is different than before, either the preview takes longer than before or there is a shorter timeout. And this is a problem because it is not possible to develop a pipeline with more complex queries.

In my case, there is only code 400 or 408. But it's probably related to some timeout problem, because the error occurs with more complex and longer queries.

josef78_1-1749640946286.png

or

josef78_0-1749728829849.png

 

 

josef78
Memorable Member
Memorable Member

Same problem here, on Copy Activity. When I try preview on source of copy activity (Oracle DB via on-premise gw), it returns error 400 or 408. It happens in case of more complex queries.

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