Re: lazy detoasting - Mailing list pgsql-hackers

From Peter Eisentraut
Subject Re: lazy detoasting
Date
Msg-id b46df083-0e20-536b-12f9-0b270ebb48ee@2ndquadrant.com
Whole thread Raw
In response to Re: lazy detoasting  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: lazy detoasting  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On 5/12/18 17:25, Tom Lane wrote:
> Anyway, attached is a revised patch.  I found a test case for
> expanded_record_set_fields(), too.

Thank you for fixing this up.

In reviewing the committed patch, I noticed that in ER_get_flat_size()
you have removed the PG_DETOAST_DATUM() call and let
expanded_record_set_field_internal() do the de-toasting work.  I had
considered that too, but my impression is that the purpose of the
PG_DETOAST_DATUM() is to de-compress for the purpose of size
computation, whereas expanded_record_set_field_internal() only does the
inlining of externally stored values and doesn't do any explicit
decompression.  Is this correct?

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services


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