MySQL tracker store gives error VARCHAR requires a length on dialect mysql

Hi Palash,

I just had the exact same problem. It seems like an issue with the ‘sqlalchemy’ package when it tries to create the table column because no lenght is specified.

I found a ‘temporary’ solution:

Locate the following file:

~/.local/lib/python3.6/site-packages/sqlalchemy/dialects/mysql/ (might not be the same exact path) and right after the line: visit_VARCHAR

add the following:

if type_.length is None:
    type_.length = 1024 # change 1024 to whatever lenght value you need

Save the file and run rasa again. The table is created, and all varchar columns will have that exact size. I hope you can move on with this solution for the moment.


(Don’t forget this is a kind of ‘hack’ so once your table is created, you can actually remove those two lines.)