A church is a cathedral if it's a bishop's seat, which GP's churches are not. But it seems silly to characterize the Sagrada Familia as "minor".
https://en.wikipedia.org/wiki/Basilicas_in_the_Catholic_Chur...
St. Paul Outside-the-Walls was completed in 1840! Almost yesterday! However, re-consecration and construction continued after that. Interestingly, it seems that an automatic fire-detection and suppression system had been installed in the 19th century.