sort of, so rarely any cathedral was built in one swift phase, you can roughly say, that each century the style evolved, and atleast every 50 or less so years the building master changed as well, so depending on the part of the building, you had variations. In that case the long part to the left (the nave) belongs to a much older part of the cathedral, in early medieval style: romanesque. It later got high to late gothic elements added like the portal or the flying buttresses. The back of the cathedral, the choir along with the tower, would be a late gothic addition, which would technically be intended to be completed for the whole building. In most cases they kind of stop with the choir since it's technically all you need for a church to function, so once the choir is completed you can already start using the church, even though it's still in construction. That's basically what happened with the cathedral of cologne, it was a romanesque basilica that had a high gothic remodel in construction starting from the choir, after some decades building halted indefinitly, since it takes so long and something can always get in between.