Обсуждение: pgsql: tableam: Move heap-specific logic from needs_toast_table belowt

tableam: Move heap-specific logic from needs_toast_table below tableam.

This allows table AMs to completely suppress TOAST table creation, or
to modify the conditions under which they are created.

Patch by me.  Reviewed by Andres Freund.

Discussion: http://postgr.es/m/CA+Tgmoa4O2n=yphqD2pERUnYmUO84bH1SqMsA-nSxBGsZ7gWfA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1171d7d58545f26a402f76a05936d572bf29d53b

Modified Files
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src/backend/access/heap/heapam_handler.c | 53 ++++++++++++++++++++++++++++++++
src/backend/catalog/toasting.c           | 50 ++----------------------------
src/include/access/tableam.h             | 20 ++++++++++++
3 files changed, 76 insertions(+), 47 deletions(-)