Increase in dataset size due to change of the columns dtypes after the replacement of a table

[F_K21]

Hello all,

I have a pbix file and when I replaced a table with another table with the same columns, same number of rows, almost same content from the advanced editor via M code (I just changed the name of the table as both tables are at yhe same database), the dataset size was increased from 800 MB to 1.5 GB.

The pbix file also contains other tables.

By using dax studio, I observed that the data types of a lot of columns from the different tables changed which I supposed that had a result the increase in the dataset size.I retrieve the data from microsoft sql server and I have set the dtypes of the columns to be the same as the first table  but the problem still exists.

Also,  the size of hidden date tables was increased too after the table replacement.

My question is if you know how I can keep the same dtypes at the columns of the tables as they were before the table replacement.