Postgresql vs MySQL - which is better for query joining and writing data (inserts)

Question

I need to create a database that will contain 50M records in one table (there will be other tables with fewer records). I am more worried about attaching queries and writing data (inserts) to the database. There will be fewer updates and requests will be deleted.

I read this article about comparing Postgresql versus MySQL.

I also went through the links.

Postgres 9.1 vs Mysql 5.6 InnoDB?

https://stackoverflow.com/questions/110927/would-you-recommend-postgresql-over-mysql

How different is PostgreSQL from MySQL?

MySQL vs PostgreSQL Wiki

MySQL vs PostgreSQL: why MySQL is superior to PostgreSQL

My problem is some stackoverflow links. Some people say that Mysql is better and vice versa.

Since I'm more interested in joining and writing data to a database, which is better for me? Postgresql vs MySQL? What approaches should be used to create such a database?

Given that, please do not consider this as another Postgresql vs MySQL question. I did my research, and I'm only interested in joining queries and writing data to a database script. I also found out that PostgreSQL is better suited for GIS data ..