Date column not recognised as Date due to presence of the year 1800 & 3000
My table contains a column with dates mostly in the range of 1990-2020, however a portion contains the date '01-01-1800' or '31-12-3000' (due to various reasons, these dates should not be changed). However, Qlik therefore doesn't recognise my date column as Date, and prevents me from applying it on e.g. the Date Picker.
The column does get recognised as Date by Qlik when the rows containing dates 01-01-1800 & 31-12-3000 are removed from the table, however I don't want to lose these observations.
Therefore my question is: How can I let Qlik recognise 01-01-1800 & 31-12-3000 as dates, such that the whole column while be eligible as Date?
I read about the Tag function, however I'm not sure how to specifically apply this.