Horton

Re: Pluggable Storage - Andres's take

Amit Khandekar <amitdkhan.pg@gmail.com>

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From: Amit Khandekar <amitdkhan.pg@gmail.com>
To: Dmitry Dolgov <9erthalion6@gmail.com>
Cc: Andres Freund <andres@anarazel.de>, Haribabu Kommi <kommi.haribabu@gmail.com>, Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>, Peter Geoghegan <pg@bowt.ie>, Alvaro Herrera <alvherre@2ndquadrant.com>, Alexander Korotkov <a.korotkov@postgrespro.ru>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2019-01-14T13:06:59Z
Lists: pgsql-hackers 
Thanks for the patch updates.

A few comments so far from me :

+static void _selectTableAccessMethod(ArchiveHandle *AH, const char
*tablespace);
tablespace => tableam

+_selectTableAccessMethod(ArchiveHandle *AH, const char *tableam)
+{
+       PQExpBuffer cmd = createPQExpBuffer();
createPQExpBuffer() should be moved after the below statement, so that
it does not leak memory :
if (have && strcmp(want, have) == 0)
return;

char    *tableam; /* table access method, onlyt for TABLE tags */
Indentation is a bit misaligned. onlyt=> only



@@ -2696,6 +2701,7 @@ ReadToc(ArchiveHandle *AH)
                        te->tablespace = ReadStr(AH);

te->owner = ReadStr(AH);
+  te->tableam = ReadStr(AH);

Above, I am not sure about the this, but possibly we may require to
have archive-version check like how it is done for tablespace :
if (AH->version >= K_VERS_1_10)
   te->tablespace = ReadStr(AH);

So how about bumping up the archive version and doing these checks ?
Otherwise, if we run pg_restore using old version, we may read some
junk into te->tableam, or possibly crash. As I said, I am not sure
about this due to lack of clear understanding of archive versioning,
but let me know if you indeed find this issue to be true.

Commits

  1. Add default_table_access_method to postgresql.conf.sample.

  2. tableam: Avoid relying on relation size to determine validity of tids.

  3. tableam: Don't assume that every AM uses md.c style storage.

  4. Allow pg_class xid & multixid horizons to not be set.

  5. Fix slot type issue for fuzzy distance index scan over out-of-core table AM.

  6. tableam: comment and formatting fixes.

  7. table: docs: fix typos and grammar.

  8. tableam: basic documentation.

  9. Only allow heap in a number of contrib modules.

  10. tableam: Add table_finish_bulk_insert().

  11. tableam: sample scan.

  12. tableam: bitmap table scan.

  13. tableam: Move heap specific logic from estimate_rel_size below tableam.

  14. tableam: VACUUM and ANALYZE support.

  15. tableam: relation creation, VACUUM FULL/CLUSTER, SET TABLESPACE.

  16. tableam: Support for an index build's initial table scan(s).

  17. tableam: Add table_get_latest_tid, to wrap heap_get_latest_tid.

  18. tableam: Add helper for indexes to check if a corresponding table tuples exist.

  19. tableam: Add and use table_fetch_row_version().

  20. tableam: Use in CREATE TABLE AS and CREATE MATERIALIZED VIEW.

  21. Ensure sufficient alignment for ParallelTableScanDescData in BTShared.

  22. Don't reuse slots between root and partition in ON CONFLICT ... UPDATE.

  23. Use a virtual rather than a heap slot in two places where that suffices.

  24. Store tuples for EvalPlanQual in slots, rather than as HeapTuples.

  25. Use slots in trigger infrastructure, except for the actual invocation.

  26. Store table oid and tuple's tid in tuple slots directly.

  27. Allow to use HeapTupleData embedded in [Buffer]HeapTupleTableSlot.

  28. Add ExecStorePinnedBufferHeapTuple.

  29. Add ArchiveOpts to pass options to ArchiveEntry

  30. Rename RelationData.rd_amroutine to rd_indam.

  31. Rephrase references to "time qualification".

  32. Move remaining code from tqual.[ch] to heapam.h / heapam_visibility.c.

  33. Move generic snapshot related code from tqual.h to snapmgr.h.

  34. Remove superfluous tqual.h includes.

  35. Don't duplicate parallel seqscan shmem sizing logic in nbtree.

  36. Move vacuumlazy.c into access/heap.

  37. Support parallel bitmap heap scans.