postgresql-8.3

I have a function in Postgres 8.3.5 that selects data from multiple tables and dumps the result in a single table: create or replace function test_function_2(startdate timestamp, enddate timestamp) returns void as $$ begin delete from cl_final_report; INSERT INTO cl_final_report SELECT b.batchkey AS batchnumber, pv.productkey, p.name AS productname, avg(r.value) AS avgchemlean, sum(r.auxvalue) AS totalweight, max(o.time) AS timecompleted FROM result r LEFT JOIN physicalvalue pv ON r.physicalvaluekey = pv.physicalvaluekey LEFT JOIN product p ON pv.productkey = p.productkey LEFT JOIN object o ON

This is a postgresql problem. PostgreSQL 8.3.3 on i686-redhat-linux-gnu, compiled by GCC gcc (GCC) 3.4.6 20060404 (Red Hat 3.4.6-9). The table looks like: date_time other_column 2012-11-01 00:00:00 ... 2012-11-02 01:00:00 ... 2012-11-02 02:00:00 ... 2012-11-02 03:00:00 ... 2012-11-02 04:00:00 ... 2012-11-03 05:00:00 ... 2012-11-03 06:00:00 ... 2012-11-05 00:00:00 ... 2012-11-07 00:00:00 ... 2012-11-07 00:00:00 ... ... I want to select at most 3 records per day from a specific date range. For example, I want to select at most 3 records from 2012-11-02 to 2012-11-05. The expected result would be