[bug report] About create table like feature's bug

From: dengkai <784523565(at)qq(dot)com>
To: pgsql-bugs <pgsql-bugs(at)lists(dot)postgresql(dot)org>
Subject: [bug report] About create table like feature's bug
Date: 2025-10-31 07:14:57
Message-ID: tencent_83CB623256F68B1CBE13201DE8C51BFB8006@qq.com
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hi, all

&nbsp; When I use 'create table like' command to create a table with 'including indexes' options, database return
an unexpected result. Look at the following sql statement.

postgres=# create table t1(c1 int, c2 char(10));

CREATE TABLE

postgres=# create index idx1 on t1(c1);

CREATE INDEX

postgres=# \d+ t1

&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Table "public.t1"

&nbsp;Column | &nbsp; &nbsp; Type&nbsp; &nbsp; &nbsp; | Collation | Nullable | Default | Storage&nbsp; | Compression | Stats target | Description

--------+---------------+-----------+----------+---------+----------+-------------+--------------+-------------

&nbsp;c1 &nbsp; &nbsp; | integer &nbsp; &nbsp; &nbsp; | &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; | &nbsp; &nbsp; &nbsp; &nbsp; | plain&nbsp; &nbsp; | &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |

&nbsp;c2 &nbsp; &nbsp; | character(10) | &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; | &nbsp; &nbsp; &nbsp; &nbsp; | extended | &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |

Indexes:

&nbsp; &nbsp; "idx1" btree (c1)

Access method: heap


postgres=# create table t2(like t1 including indexes);

CREATE TABLE

postgres=# \d+ t2

&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Table "public.t2"

&nbsp;Column | &nbsp; &nbsp; Type&nbsp; &nbsp; &nbsp; | Collation | Nullable | Default | Storage&nbsp; | Compression | Stats target | Description

--------+---------------+-----------+----------+---------+----------+-------------+--------------+-------------

&nbsp;c1 &nbsp; &nbsp; | integer &nbsp; &nbsp; &nbsp; | &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; | &nbsp; &nbsp; &nbsp; &nbsp; | plain&nbsp; &nbsp; | &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |

&nbsp;c2 &nbsp; &nbsp; | character(10) | &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; | &nbsp; &nbsp; &nbsp; &nbsp; | extended | &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; |

Indexes:

&nbsp; &nbsp; "t2_c1_idx" btree (c1)

Access method: heap

postgres=# select version();

&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; version&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;

------------------------------------------------------------------------------------------------------------

&nbsp;PostgreSQL 16devel on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-44), 64-bit

(1 row)

I did not use 'including storage' option in 'create table like' statement, but there is an extended attribute on t2.c2.
It seems that the 'including storage' option is not effective, the default behavior of database is to bring the storage
attribute from original table columns to the new table.

I found this phenomenon on pg15.5 version. And it should also be present on pg18. Is this a bug？
I look forward to your reply.

best regards
dengkai

dengkai
784523565(at)qq(dot)com

&nbsp;

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