Please recommend me the best bulk-delete option

Hi All,

I'm using PostgreSQL 8.1.4. I've 3 tables: one being the core (table1), others are dependents (table2,table3). I inserted 70000 records in table1 and appropriate related records in other 2 tables. As I'd used CASCADE, I could able to delete the related records using DELETE FROM table1; It works fine when the records are minimal in my current PostgreSQL version. When I've a huge volume of records, it tries to delete all but there is no sign of deletion progress for many hours! Whereas, bulk import, does in few minutes. I wish to do bulk-delete in reasonable minutes. I tried TRUNCATE also. Like, TRUNCATE table3, table2,table1; No change in performance though. It just takes more time, and no sign of completion! From the net, I got few options, like, deleting all constraints and then recreating the same would be fine. But, no query seems to be successfully run over 'table1' when it's loaded more data!
Please recommend me the best solutions to delete all the records in minutes.

CREATE TABLE table1(
t1_id SERIAL PRIMARY KEY,
disp_name TEXT NOT NULL DEFAULT '',
last_updated TIMESTAMP NOT NULL DEFAULT current_timestamp,
UNIQUE(disp_name)
) WITHOUT OIDS;

CREATE UNIQUE INDEX disp_name_index on table1(upper(disp_name));

CREATE TABLE table2 (
t2_id SERIAL PRIMARY KEY,
t1_id INTEGER REFERENCES table1 ON DELETE CASCADE,
type TEXT
) WITHOUT OIDS;

CREATE TABLE table3 (
t3_id SERIAL PRIMARY KEY,
t1_id INTEGER REFERENCES table1 ON DELETE CASCADE,
config_key TEXT,
config_value TEXT
) WITHOUT OIDS;

Regards,
Siva.

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