PostgreSQL query to rename and change column type with single query

Question

In PostgreSQL if I need to rename and change a column data type, I run two separate queries to do so.

To rename:

AL         


        

Answer 1

In PostgreSQL, ALTER TABLE can take a series of operations. So:

ALTER TABLE  RENAME  TO ;
ALTER TABLE  ALTER COLUMN  TYPE ;

is the same as

ALTER TABLE  
  ALTER COLUMN  TYPE 
  RENAME  TO ;

However... why? IIRC the rename won't cause a full-table scan, so there's no benefit over just doing the two statements separately, within one transaction. What problem are you actually trying to solve with this?