Load ... FROM CONFIG do not return error when it failed to load by PK violation

[takaidohigasi]

• A clear description of the issue
  Load ... from CONFIG do not return error when we try to load PK violated mysql_servers and failed to sync.
• ProxySQL version

$ proxysql --version
2025-07-08 17:25:51 [INFO] Using OpenSSL version: OpenSSL 3.2.2 4 Jun 2024
ProxySQL version 3.0.1-420-g2c26a42, codename Truls

• OS version

 $ cat /etc/redhat-release
Rocky Linux release 9.5 (Blue Onyx)

• The steps to reproduce the issue

1. prepare initial mysql_servers and start ProxySQL

mysql_servers=
(
    {
        address         = "test.local"
        port            = 3306
        hostgroup       = 0
        weight          = 1
        status          = "ONLINE"
    },
    {
        address         = "test2.local"
        port            = 3306
        hostgroup       = 0
        weight          = 1
        status          = "ONLINE"
    },
    {} )

2. change config

mysql_servers=
(
    {
        address         = "test.local"
        port            = 3306
        hostgroup       = 0
        weight          = 1
        status          = "ONLINE"
    },
    {
        address         = "test.local"
        port            = 3306
        hostgroup       = 0
        weight          = 1
        status          = "ONLINE"
    },
    {} )

3. load data

mysql> LOAD MYSQL SERVERS FROM CONFIG;
Query OK, 2 rows affected (0.01 sec)

mysql> select * from runtime_mysql_servers;
returns original value.

[takaidohigasi]

https://github.com/sysown/proxysql/blob/v3.0/lib/Admin_Handler.cpp#L1687-L1717

[takaidohigasi]

https://github.com/sysown/proxysql/blob/v3.0/lib/ProxySQL_Config.cpp#L1017