If you are willing to forego 3rd normal form and just duplicate data like mad, and have a million column like a giant excel sheet, then you really don’t need foreign keys.
If you are willing to forego 3rd normal form and just duplicate data like mad, and have a million column like a giant excel sheet, then you really don’t need foreign keys.
MyISAM I think was the table type that did NOT support FK constraints and was blazing fast. InnoDB had FK constraints.
You would fully normalize, use proper joins etc. But without FK constraints you could end up with orphan data... Not the worst thing in the world, depending on how the joins in your system were structured.
Care and diligence were the order of the day. You had to know your schema and make sure you were doing the RIGHT thing at all points in the stack.
If you duplicate data like mad, how do you ensure that the duplicates are in sync? If you avoid UPDATEs I could maybe see it working.