Question: what is ibtmp1 file in mysql?
Answer: If you're running MySQL 5.7, you might have noticed the ibtmp1 file located in the datadir, and you might be wondering exactly what this file is. In 5.7, InnoDB added a separate tablespace for all non-compressed InnoDB temporary tables. This new tablespace is named ibtmp1 and is located in the datadir by default.