> 1. Allow relpages to be set to -1 (partitioned tables with partitions have 
> this value after ANALYZE).
> 2. Turn off autovacuum on tables (where possible) if they are going to be the 
> target of pg_set_relation_stats().
> 3. Allow pg_set_relation_stats to continue past an out-of-range detection on 
> one attribute, rather than immediately returning false

Thank you for developing this feature.
If the relpages option contains -1 only for partitioned tables, shouldn't 
pg_set_relation_stats restrict the values that can be
specified by table type? The attached patch limits the value to -1 or more if 
the target
is a partition table, and 0 or more otherwise.
Changing relpages to -1 on a non-partitioned table seems to significantly 
change the execution plan.

---
postgres=> EXPLAIN (COSTS OFF) SELECT * FROM data1 WHERE c1=1000;
              QUERY PLAN
--------------------------------------
Index Scan using data1_pkey on data1
   Index Cond: (c1 = 1000)
(2 rows)

postgres=> SELECT pg_set_relation_stats('data1', relpages=>-1);
pg_set_relation_stats
-----------------------
t
(1 row)

postgres=> EXPLAIN (COSTS OFF) SELECT * FROM data1 WHERE c1=1000;
              QUERY PLAN
---------------------------------------
Bitmap Heap Scan on data1
   Recheck Cond: (c1 = 1000)
   ->  Bitmap Index Scan on data1_pkey
         Index Cond: (c1 = 1000)
(4 rows)
---

Regards,
Noriyoshi Shinoda

From: Corey Huinker <[email protected]>
Sent: Saturday, October 19, 2024 10:00 AM
To: Jeff Davis <[email protected]>
Cc: Shinoda, Noriyoshi (SXD Japan FSIP) <[email protected]>; jian he 
<[email protected]>; Matthias van de Meent 
<[email protected]>; Bruce Momjian <[email protected]>; Tom Lane 
<[email protected]>; Nathan Bossart <[email protected]>; Magnus 
Hagander <[email protected]>; Stephen Frost <[email protected]>; Ashutosh 
Bapat <[email protected]>; Peter Smith <[email protected]>; 
PostgreSQL Hackers <[email protected]>; [email protected]
Subject: Re: Statistics Import and Export



Patch that allows relation_statistics_update to continue after one failed stat 
(0001) attached, along with bool->void change (0002).

Once more, with feeling:

Attachment: pg_set_relation_stats_patch_v1.diff
Description: pg_set_relation_stats_patch_v1.diff

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