Expression Error: we cannot convert value null to type list

[mbasha_123]

Getting Expression Error when loading Data from SQL using a Custom Connector. below is the Screenshot of the error

Thanks in advance

[adeelaziz]

Nice and simple solution!  Thanks.

[v-yanjiang-msft · Accepted solution]

Hi @mbasha_123 ,

It's there is a "null" value in the column, the "null" value is not list type, it can't execute the step you applied.

For example this column

When I select expand button>Extract Values

The null row get an error the same with yours.

Here's my solution, add the function try otherwise in the code.

Here's the original code which return an error.

= Table.TransformColumns(New, {"Name", each Text.Combine(List.Transform(_, Text.From)), type text})

Add try otherwise like this:

= Table.TransformColumns(New, {"Name", each try Text.Combine(List.Transform(_, Text.From)) otherwise null , type text})

Get the result.

I attach my sample below for your reference.

Best Regards,
Community Support Team _ kalyj

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