expanded Column (Table.ExpandTableColumn) breaks query folding

[Anonymous]

Hi, So I am extracting data from Sql database and my main goal is to perform each step in power query WITHOUT BREAKING THE QUERY FOLDING. But if you lok at the screenshots below it breakes the query while expanding the column using Table.ExpandTableColumn function. can anyone guide me whats the issue here and how to resolve these merginf queries and expanding columns in such a way that it does not break query folding.

PFB the screenshot of step where it breaks the query folding,

PFB the m code,

Thanks in advance.

[edhans]

Expanding the column should work unless there is some unusual data type that is being expanded. If you don't expand the column, the Merge will actually break folding, but it is fixed on the expand operation.

However, if the table you are merging isn't folding, that will break folding too. So if the NewColumn you added in SaleItemProd broke folding, or the query SaleItemProd broke folding earlier, that is the issue. You cannot continue folding unless both the existing and merged queries were folding at the point of the Merge.

[edhans]

@Anonymous did any of this help? Did you confirm that both tables in the merge operation were folding before the merge?