When you connect a data source, Tableau automatically infers the type of each column of your data. Whether it's Number (decimal), Number (whole), String, Boolean, etc. A few questions about this:

1) Has Tableau ever misclassified one (or more) columns of your data with their automatic labeling? If so, would you please give details?

2) Do you feel that these data type options can be improved? For example, Tableau doesn't seem to be distinguishing between unordered categorical data and ordinal data.

Thanks!

1. Yes, it sometimes does that. I think it depends on the data source. For RDBMS it is likely that it takes the data type from the database (so the column type is typically accurate). For text/csv, it probably does a scan of the top certain lines to guestimate the type. It is similar to the text import wizard of the SQL, etc. other similar tool. (A Tableau user of 4+ years)
2. I am not sure if it is relevant to many of the Tableau users; many databases don't have that distinction either; I think it is more helpful for someone working in machine learning, etc.?

Data types characterize the data values into its definite type. Some data values are only text (eg. “DataFlair”) so their data type will be a string as it only contains characters. While some data values have whole numbers (eg. 5550) and so their data type is an integer. If a data value is in the form of a date or time (eg. 22/02/2019 or 03:25:40) then the data type date/time is assigned to it. In a similar way, every data value will fall under a certain category of the data type. Tableau also has a set of data types based on which it characterizes every data value present in it as field values either from a live data connection or as a data extract from the data source.

There are primarily seven data types used in Tableau. Tableau automatically detects the data types of various fields as soon as new data gets uploaded from source to Tableau and assigns it to the fields. You can also modify these data types after uploading your data into Tableau by options available in the:

1. String values
2. Number (Integer) values
3. Date values
4. Date & Time values
5. Boolean values
6. Geographic values
7. Cluster or mixed values