SELECT Query returns empty

Hi All,

I would really appreciate if any one can help me out on the
problem that I am facing with PostgreSQL.

The following is the system (Dell laptop) configuration:

Windows XP - SP2, Intel Core 2Duo, 2GB RAM

PostgreSQL v 8.3.3

The scenario:
There are two separate processes - one (P1) inserting (not
updating) data to a table at a high rate (around one record in 10ms) and
another (P2) selecting the data from the same table for further
processing. P1 and P2 use separate connection to the Database and P1
sends a trigger to P2 after inserting the data to the PostgreSQL.

The issue:

P2 tries to query the data from the table, and the result
set is empty. I modified the logic to send the trigger only after making
sure that P1 can successfully query the last record it inserted.

I would like to know why P1 can retrieve the data from the table while
P2 can't.

Thanks and Regards

-Bright