Can't convert table value to string in ADF

Kresten 0
Viewed 50

I'm trying to loop over data in an SQL table, but when I'm trying to use the value inside a foreach loop action using the @item() i get the error:

"Failed to convert the value in 'table' property to 'System.String' type. Please make sure the payload structure and value are correct."

So the row value can't be converted to a string. Could that be my problem? and if so, what can I do about it?

Here is the pipeline:

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azure-data-factory-pipeline azure-data-factory
1 Answers

I reproduced the above scenario with SQL table containing table names in lookup and csv files from ADLS gen2 in copy activity and got the same error.

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The above error arises when we gave the lookup output array items directly into a string parameter inside ForEach.

If we look at the below lookup output,

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The above value array is not a normal array, it is an array of objects. So, @item() in 1st iteration of ForEach means one object { "tablename": "sample1.csv" }. But our parameter expects a string value and that's why it is giving the above error.

To resolve this, give @item().tablename which will give our table names in every iteration inside ForEach.

My repro for your reference:

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I have given same in sink also and this is my output.

Pipeline Execution

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Copied data in target

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Rakesh Govindula0
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