Habing trouble with copy activity in pipeline with error ' Failure happened on 'destination' side.'

[Rikin_Basu]

I am trying to execute a copy activity where I am trying bring inmultiple tables from Oracle database through an on-prem gateway.

However I am getting the below error :
Failure happened on 'destination' side.

'Type=System.InvalidOperationException,

Message=Cannot downgrade the minimum reader version,

Source=Microsoft.DataTransfer.ClientLibrary,'

Can anyone help me understand what this error means and what should I be looking for in my destination lakehouse to fix this error ?

[KNP · Accepted solution]

I've found these errors to be very misleading at times.

For troubleshooting:

On the source side, does the 'Preview Data' load for you?

Is the destination set to overwrite or append?

If it is set to OverWrite, have a look in the code from the view menu and check that it doesn't say OverwriteSchema.

If it does, you can change it to Overwrite and see if it runs.

[mattstacy]

Hey @KNP, this worked for me as I had the same issue. Are you able to explain what the difference between OverwriteSchema and OverWrite is? It would also be helpful to understand why it selects OverwriteSchema in the UI that requires overwriting it in the JSON.

[KNP]

Hey @mattstacy,

My understanding of the two (which may not be correct or complete) is:

OverWrite is overwrite the data only.

OverwriteSchema is overwrite the data and any changes to the schema (new columns, data type changes, column names etc.)

I've had varying results when creating jobs and haven't found a consistent pattern when these errors occur. It seems to be getting better though and I've had less of these issues lately.