How can I check conflictive packages before install

[xuta]

Because I am using both of repos are stable and squeeze. Sometime I meet conflict when install new packages.
I.E: When I need install postgresql by aptitude, if I choose version 8.3, it's ok, but if I choose version 8.4, I see conflicting packages.

Now, I need write a shell script which allow me check conflicting some version of a package before choose one of them automatically for installing.
Thank you in advance.

[dino99]

synaptic will automatically popup if a conflict exist

[xuta]

It's not good solution which I hope.
I hope available some commands which allow me to check it, then use this result for auto choice version.

[dino99]

It's not good solution which I hope.
I hope available some commands which allow me to check it, then use this result for auto choice version.

Might be clearer about your needs:

sqeeze= debian not ubuntu
if you need latest package release, either compile it or search an already compiled on a ppa, so other solutions bring you with breakage soon or later

https://launchpad.net/ubuntu/+ppas

[xuta]

In fact, I want to ask this question for Debian system, but if I use Ubuntu with stable + backport repos, everything are same problem.

[xuta]

In fact, I want to ask this question for Debian system, but if I use Ubuntu with stable + backport repos, everything are same problem.

[xuta]

In fact, I want to ask this question for Debian system, but if I use Ubuntu with stable + backport repos, everything are same problem.

[xuta]

In fact, I want to ask this question for Debian system, but if I use Ubuntu with stable + backport repos, everything are same problem.

[xuta]

In fact, I want to ask this question for Debian system, but if I use Ubuntu with stable + backport repos, everything are same problem.

[xuta]

My network have some problem, but I cannot remove duplicate posted, so Admin/mod help me delete them.
Many thanks.