On Feb 27, 2015 5:02 PM, "Alvaro Herrera" <alvhe...@2ndquadrant.com> wrote: > > Arthur Silva wrote: > > > Sorry to intrude, I've been following this post and I was wondering if it > > would allow (in the currently planed form or in the future) a wider set of > > non-rewriting DDLs to Postgres. For example, drop a column without > > rewriting the table. > > Perhaps. But dropping a column already does not rewrite the table, only > marks the column as dropped in system catalogs, so do you have a better > example. > > One obvious example is that you have > > CREATE TABLE t ( > t1 int, > t3 int > ); > > and later want to add t2 in the middle, the only way currently is to > drop the table and start again (re-creating all dependant views, FKs, > etc). With the patch you will be able to add the column at the right > place. If no default value is supplied for the new column, no table > rewrite is necessary at all. > > -- > Álvaro Herrera http://www.2ndQuadrant.com/ > PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
Cool! I didn't know I could drop stuff without rewriting. Ya, that's another example, people do these from GUI tools. That's a nice side effect. Cool (again)!