Need an option to disable server-side prepares

[vitalif]

Hi!
Recently, when testing an application that does huge INSERTs (~60 mb in a single query) I discovered that these queries were much slower with nodejs pg-native driver than with just plain psql < file.sql. By "much slower" I mean 7-11 seconds with psql and 60-90 seconds with nodejs. It doesn't reproduce with all server configurations - I assume it reproduces better when the server has limited RAM and slow disks (HDDs).
After some digging I finally captured network traffic between the client and postgresql server and I discovered that nodejs and psql really send queries in different ways!

nodejs pg-native:

psql:

This test was done with pg-native, but the same also happens with pg.
'Q' is the "query" message and 'P' is the "parse" message. This means that nodejs seems to send a prepare+execute pair instead of just query.

So I obviously want to disable this behaviour - can you please add an option for it?
(PDO in PHP has one, it's called PDO::ATTR_EMULATE_PREPARES)

UPD: Rechecked with pg. It's OK, it was slow in my case because I actually had some bind variables there. With pg-native, however, the case is valid - prepare emerges out of nowhere :).

[charmander]

You should use UNNEST or COPY instead of building a dynamic query.

[vitalif]

I'm fine with INSERT. I just need the correct behavior from the driver.