Difference between EXPLAIN ANALYZE SELECT ... total runtime and SELECT ... runtime

Hello,

I have strange problem.

I test/optimize my queries with EXPLAIN ANALYZE. I get for example:

Total runtime: 40.794 ms

But when I run query without EXPLAIN ANALYZE i get, for example:

Time: 539.252 ms

Query returns 33 rows. Why?

I do checks with psql connected using socket to postgresql server. No SSL.

Using PostgreSQL 8.4.4.

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Piotr Gasidło