Mageshwaran <j_mageshwaran(at)sifycorp(dot)com> writes:
> can any one tell me the major difference between 7.1.1 and 7.4.x version
> of postgresql,
Read the release notes.
http://developer.postgresql.org/pgdocs/postgres/release.html
> also please tell me what are things to considered when upgrading
> postgresql from 7.1.1 to 7.4.x.
Why in the world are you considering an upgrade from a six-year-old
release to a three-year-old release? Do yourself a favor and move
onto something more or less modern. If 8.2.4 is too bleeding-edge
for you, then 8.1.9.
regards, tom lane