It is often convenient to have columns of a table in certain order (as shown by psql or most GUI database explorers, it also affects INSERT's without columns specified behavior) so as to most significant columns to come first, semantically close columns to be grouped etc, while the columns might be added to the table in different order during development process. So, the question is - is it an acceptable way to play with pg_attribute's attnum and set it to needed value or recreate the table is the only way? On the related note - should the columns necessarily be numbered from 1 up with the step of 1?