Added prosupport function for estimating numeric generate_series rows

From: 孤傲小二~阿沐 <tsinghualucky912(at)foxmail(dot)com>
To: pgsql-hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Cc: japinli <japinli(at)hotmail(dot)com>, jian(dot)universality <jian(dot)universality(at)gmail(dot)com>
Subject: Added prosupport function for estimating numeric generate_series rows
Date: 2024-11-28 07:46:47
Message-ID: tencent_F43E7F4DD50EF5986D1051DE8DE547910206@qq.com
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Hello hackers, I saw a recent submission: Teach planner how to estimate rows for timestamp generate_series. I provide a patch for the numeric type here, and a simple test is as follows:

postgres=# explain SELECT * FROM generate_series(-25.0, -1.0, 2.0);
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; QUERY PLAN &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;
----------------------------------------------------------------------
&nbsp;Function Scan on generate_series &nbsp;(cost=0.00..0.13 rows=13 width=32)
(1 row)

postgres=# explain SELECT * FROM generate_series(-25.0, -1.0); &nbsp; &nbsp;
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; QUERY PLAN &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;
----------------------------------------------------------------------
&nbsp;Function Scan on generate_series &nbsp;(cost=0.00..0.25 rows=25 width=32)
(1 row)

postgres=#

I really want to know your thoughts, please give me feedback. Thank you.

Attachment Content-Type Size
0001-Added-prosupport-functions-for-estimating-numeric-ge.patch application/octet-stream 5.1 KB

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