I am using a sql server connection and in one table there a log dates as string which are not automatically recognized if I try to change the data type into date or datetime.
If I do so then nearly everything will be shown as null.
I created an extract in order to get the function dateparse which is usually not supported by sql server.
When I created the calculation "Calc1" there was no error inside the calculation but if I change to the sheet "data source" in Tableau I see an exclamation mark for "Calc1".
The further description says that the status is invalid!?
Does this information occurs because I'm using dateparse? Or maybe because the column "Log" has a few entries which aren't dates?
I tried to create a small example workbook but in this test case no problem occurs.
It's strange because I can use "Calc1" as filter without any issues so I don't understand why Tableau has a problem with this calculated field.
Did anybody have this issue too?