> you need to create a new table instead of modifying a column If modifying the column's type, yes. But you don't if you're just renaming, adding, or dropping

> you need to create a new table instead of modifying a column If modifying the column's type, yes. But you don't if you're just renaming, adding, or dropping a column. > column types are not checked and you can easily insert a string into numeric column. Can be fixed with CHECK constraints in the table definitions. > Also it doesn't allow you to use multiple application servers. This is mentioned in OP. > So it can be used only with small, simple sites. It can be used in a large variety of applications, but it's more appropriate for some than for others.