postgres column Alignment and Padding order

• https://www.percona.com/blog/postgresql-column-alignment-and-padding-how-to-improve-performance-with-smarter-table-design/
• https://stackoverflow.com/questions/12604744/does-the-order-of-columns-in-a-postgres-table-impact-performance
• https://stackoverflow.com/questions/2966524/calculating-and-saving-space-in-postgresql/7431468#7431468
• alignment padding: https://www.postgresql.org/docs/current/catalog-pg-type.html