Being able to order by calculated values

[AzariasB]

Is your feature request related to a problem? Please describe.
I'm using postgresql and would like to be able to execute an order by like this : order by length(my_column)

Describe the solution you'd like
Either being able to use the orderBy provided by mikro-orm : myquery.orderBy({'length(my_column)':'asc'})
or adding a new method to have the same thing as knex : myquery.orderByRaw({'length(my_column)':'asc'})

Describe alternatives you've considered
I could load all the entities and then do the sorting in typescript

Additional context
Currently, when doing order by length(my_column) I get the error : column.split is not a function
I'm using postgreql 12.3 and mikro-orm 4.0.0-alpha.9

[B4nan]

qb.orderBy({ 'length(my_column)': 'asc' }) will be supported in 4.0.0-rc.1

[AzariasB]

Wow, awesome, thanks !