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Helper II
Helper II

Refresh fails first attempt (reason : data format) and success second attempt

Hello Experts,

I'm working on a Power BI report that takes a MySQL database as its source and I'm updating the data via the gateway.

I'm facing a recurring problem that I can't find a clear explanation:

I planned two refreshes:

1st attempt at 9:00 utc

2nd attempt at 9:30 am utc

the 1st time always fails with the same error message every day and the 2nd attempt always ends successfully.

Error message :

{"error":{"code":"DM_GWPipeline_Gateway_MashupDataAccessError","pbi.error":{"code":"DM_GWPipeline_Gateway_MashupDataAccessError","parameters":{},"details":[{"code":"DM_ErrorDetailNameCode_UnderlyingErrorCode","detail":{"type":1,"value":"-2147467259"}},{"code":"DM_ErrorDetailNameCode_UnderlyingErrorMessage","detail":{"type":1,"value":"An error happened while reading data from the provider: 'Input string was not in a correct format.'"}},{"code":"DM_ErrorDetailNameCode_UnderlyingHResult","detail":{"type":1,"value":"-2147467259"}},{"code":"Microsoft.Data.Mashup.ValueError.DataSourceKind","detail":{"type":1,"value":"MySql"}},{"code":"Microsoft.Data.Mashup.ValueError.DataSourcePath","detail":{"type":1,"value":";my_database"}},{"code":"Microsoft.Data.Mashup.ValueError.Reason","detail":{"type":1,"value":"DataSource.Error"}}],"exceptionCulprit":1}}} Table: Currency.

URI du cluster:

ID d'activité:       ff2a174b-d3e4-49c4-832f-7281b0880766

ID de demande:               45421fac-d923-4f08-9193-27f00635bb68

Heure:   2023-08-08 08:39:30Z


Summary :

Code : DM_GWPipeline_Gateway_MashupDataAccessError


Table: Currency (it depends , every day can change the table)

An error happened while reading data from the provider: Input string was not in a correct format

@amitchandak  @Ritaf1983 @Ashish_Mathur  @Sahir_Maharaj  @Greg_Deckler  @TomMartens @Jihwan_Kim 


--> if the 2nd attempt refresh works fine , so we cannot talk about data format ?

New Member

I agree. I have a manual refresh in Power BI from MySQL which always fails first time with the input string in the wrong format problem. I go into Power Query editor and see the candy stripe error for the whole table. I click on another table and then click back on the problem table and it goes green (no changes made in the code). I close and apply and refresh and everything works just fine - on the third refresh(!) It seems as though Power BI thinks "this data is no good" (first time)  - "this data has a problem" (second time) - "Oh go on, I'll load it anyway" (third time). Surely this can't be the protocol?

MySQL is updated once a day by somebody else, and I'm the only one using it, so there's no conflicts or clashes. I've also ended parallel processing.


I also access the data from PowerQuery in Excel. Here I use VBA to load the data twice. First time each table (10) nearly always fails, so I have an error trap which runs the request again, which nearly always works.

Helper II
Helper II

Hello Team ,
sorry to answer late : we don't find a logical reason for the error (in the tables , in the model relationships , etc) :
at any time when we refresh the report :
the first attempt make error
the 2nd attempt refresh works fine
--> so as a temporary solution , we had schedule the report refresh for 2 times (9:00 and 9:30) and it works to finally refresh the data and we talk to the customer to ignor the first attempt

Super User
Super User



interesting that the first attempt fails and the second succeeds. Are there any processes that might be conflicting with the first refresh attempt? Maybe another process is locking a table or altering data at that time.


Also, is it possible that your MySQL DB updates/writes data at 9 UTC? Probably that is causing the issue. Try changing the schedule refresh time. See if that works. 


Also, from this doc

  • Gateway process may have restarted when the dataset refresh was in progress.


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Hello , the problem i can't confirm if the team worked in the database source (my SQL) is updating database at 9h00 but if find a temporary solution : 

1st schedule at 9h00 : fails 

2nd schedule at 9h30 : success with any problems

so logical , it cannot be a problem of confilcts but it seems at some readed data at the first time not well interpered (compiled in the format , for this reason the error message : Input string was not in a correct format) and after it works : the unique explanation that i find .


Kind Regards

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