Adding custom column causes "blank values error"

[Anonymous]

Hello,

I have a text column which contains in some rows only numeric entries and in other rows also text. I want to add now another column which takes the numeric values as they are and replaces all the text values by zeros. I do that like that:

= Table.AddColumn(#"Step before", "Column2", each try Number.From([Column1]) otherwise 0)

In the query editor this works perfectly. However as soon as I want to apply changes  I get the infamous  "Column 'Column3' in Table 'mytable' contains blank values and this is not allowed for columns on the one side of a many-to-one relationship or for columns that are used as the primary key of a table."-error.

This happens also if I break all relationships to this table. Note also that Column3 is mentioned in the error which is independent of Column1 and Column2 that are used for adding my custom column. Manually removing empty rows and nulls after adding my column also doesn't fix the problem.

Does anyone have a clue what I am doing wrong?

[Greg_Deckler]

Yeah, that doesn't make any sense if you do not have any relationships to that table.

[Anonymous]

Ok, I have to correct myself: Adding a column doesn't seem to be the source of the problem. If I manually filter out all the Text values in the column and then use 

= Table.TransformColumnTypes(#"Filtered Rows",{{"Column", type number}})

to create a numeric column it looks fine in the query editor but as soon as I apply the changes the error still appears. 

[Anonymous · Accepted solution]

Finally I found the problem myself: the column that was mentioned in the error message was also a custom added column and I had added it with "Int64.type". For whatever reason this didn't cause any issues until I changed the type of the other column. Removing the "Int64.Type" from the first column, fixed the issue - although I don't have the slightest idea why because these two columns don't have anything to do with each other.