Help with a data table split

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Hi, what’s up?
I need help with the following context:
I have a data table with 500,000 rows and it generates a spreadsheet in Excel. I need to generate 2 different Excel files based on the same data table.
Here’s what I did: I created a copy of the original data table and cleaned the data, leaving only the header, and then I try to pass to the empty copy the half to the end of the original data table, deleting the rows that were passed.
But every time I go to add the row to the copied data table, it returns the error “This row already belongs to another table”.

Can anyone help me?

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@Felipe_Almeida,

To get the headers of the datatable use dtVariable.Clone This should resolve your issue.

Thanks,
Ashok :slight_smile:

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Thanks for the quick reply.

But dtVariable.Clone still gives the same error.

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Let’s say the source datatable is dtVar. To get only the header of the source datatable, use dtVar.clone.
To get half of your source datatable, use:
dtVar.AsEnumerable.take(250000).copytodatatable
To get the remaining half, reverse your source datatable and take 250000 and reverse again.

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I have prepared this solution as an example.
The error that appears is the one about the take:

image
image822×606 19.6 KB

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Hi,
Just do these to take the split the data into 2:
i. the first 250000: dtOriginal.AsEnumerable.Take(250000).CopyToDataTable
ii. the last 250000: dtOriginal.AsEnumerable.Reverse.Take(250000).Reverse.CopyToDataTable

NB: You don’t need to Clone it. Remember to Check AddHeaders when you are Reading and Writing the data table.

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The solution proposed by @Gbenga_Odelade will solve your problem, and is the most efficient - but for posterity’s sake here is what’s causing the “already belongs to another” error.

When you try to Add Data Row and just pass the row itself, that’s an object. It’s not going to copy the data into a new datarow object and then add it to the datatable. It’s trying to add the datarow object to the datatable. But that datarow object already belongs to a datatable.

To help clarify, instead of filling in DataRow with CurrentRow, you would put the following expression into the ArrayRow property of the Add Data Row activity:
CurrentRow.ItemArray

That way you’re passing the values of the datarow, as an array, instead of the datarow object itself.

2 Likes
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Thanks for your help guys.

@Gbenga_Odelade’s reply solved my problem and provided a good solution.
@postwick’s explanation was very good and gave me a very good insight into other errors besides this one.

Thank you very much for your help :smiley:

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