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core堆栈信息如下

select * from pg_default_acl;信息如下

执行过权限设置：alter default privileges for user xxx grant select on tables to xxx2；

复现用例：
1、创建两个用户，例如test、test2
2、执行alter default privileges for user usr1 grant select on tables to usr2；
查询select * from pg_default_acl;确保结果中有defaclnamespace为0的行

openGauss=# alter default privileges for user test grant select on tables to test1;
ALTER DEFAULT PRIVILEGES
openGauss=# select * from pg_default_acl;
 defaclrole | defaclnamespace | defaclobjtype |            defaclacl
------------+-----------------+---------------+----------------------------------
      16384 |               0 | r             | {test=arwdDxt/test,test1=r/test}
(1 row)

3、执行gs_dump

[upgrade@sdr-0001 ~]$ gs_dump postgres  -p 15300 -f dump.sql
Segmentation fault

数据库版本：
gaussdb (openGauss 6.0.0 build 995b5e4c) compiled at 2024-05-28 00:10:11 commit 0 last mr
验收过程：
openGauss=# create user test1 identified by 'passwd@123';
CREATE ROLE
openGauss=# create user test identified by 'passwd@123';
CREATE ROLE
openGauss=# alter default privileges for user test grant select on tables to test1;
ALTER DEFAULT PRIVILEGES
openGauss=# alter default privileges for user test grant select on tables to test1;
ALTER DEFAULT PRIVILEGES
openGauss=# select * from pg_default_acl ;
defaclrole | defaclnamespace | defaclobjtype | defaclacl
------------+-----------------+---------------+----------------------------------
16388 | 0 | r | {test1=r/test,test=arwdDxt/test}
(1 row)
gs_dump postgres -p 60019 -f dump.sql
gs_dump[port='60019'][postgres][2024-06-03 15:08:06]: Begin scanning database.
Progress: [==================================================] 100% (38/37, cur_step/total_step). finish scanning database
gs_dump[port='60019'][postgres][2024-06-03 15:08:06]: Finish scanning database.
gs_dump[port='60019'][postgres][2024-06-03 15:08:06]: Start dumping objects
Progress: [==================================================] 100% (4828/4828, dumpObjNums/totalObjNums). dump objects
gs_dump[port='60019'][postgres][2024-06-03 15:08:06]: Finish dumping objects
gs_dump[port='60019'][postgres][2024-06-03 15:08:06]: dump database postgres successfully
gs_dump[port='60019'][postgres][2024-06-03 15:08:06]: total time: 209 ms

3.0.5版本
3.0.5B009]$ gsql -d postgres -p 60025 -r
gsql ((openGauss 3.0.5 build dd00b538) compiled at 2024-05-29 12:03:03 commit 0 last mr )
Non-SSL connection (SSL connection is recommended when requiring high-security)
Type "help" for help.

openGauss=#
openGauss=#
openGauss=# create user test1 identified by 'passwd@123';
CREATE ROLE
openGauss=# create user test identified by 'passwd@123';
CREATE ROLE
openGauss=# alter default privileges for user test grant select on tables to test1;
ALTER DEFAULT PRIVILEGES
openGauss=# select * from pg_default_acl ;
defaclrole | defaclnamespace | defaclobjtype | defaclacl
------------+-----------------+---------------+----------------------------------
16388 | 0 | r | {test1=r/test,test=arwdDxt/test}
(1 row)

openGauss=# exit
openGauss-# \q
[lihj@kwemhisprc01300 3.0.5B009]$ gs_dump postgres -p 60025 -f dump.sql
gs_dump[port='60025'][postgres][2024-06-03 16:35:48]: The total objects number is 420.
gs_dump[port='60025'][postgres][2024-06-03 16:35:48]: [100.00%] 420 objects have been dumped.
gs_dump[port='60025'][postgres][2024-06-03 16:35:48]: dump database postgres successfully
gs_dump[port='60025'][postgres][2024-06-03 16:35:48]: total time: 1975 ms