Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

FILE: /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Core/Db.class.php 　LINE: 162

[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Core/Db.class.php (162) DbMysql->connect(Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2))
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Driver/Db/DbMysql.class.php (95) Db->initConnect()
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Driver/Db/DbMysql.class.php (215) DbMysql->query()
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Core/Model.class.php (135) DbMysql->getFields(SHOW COLUMNS FROM `qf_config`)
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Core/Model.class.php (123) Model->flush(qf_config)
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Core/Model.class.php (1174) Model->_checkTableInfo()
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Core/Model.class.php (98) Model->db()
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Common/common.php (294) Model->__construct(0, )
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/App/Lib/Action/Home/BaseAction.class.php (10) M(config, , )
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/App/Lib/Action/Home/PublicAction.class.php (6) BaseAction->__construct(config)
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/App/Lib/Action/Home/CustomAction.class.php (10) PublicAction->__construct()
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Common/common.php (321) CustomAction->__construct(Article, Article)
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Core/App.class.php (103) A()
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Core/App.class.php (207) App::exec()
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Lib/Core/Think.class.php (39) App::run(Home/Custom)
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Common/runtime.php (242) Think::start()
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/ThinkPHP.php (30) require(/home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/Common/runtime.php)
[21-05-14 05:34:05] /home/unioncod/domains/unioncoding.com/public_html/index.php (31) require(/home/unioncod/domains/unioncoding.com/public_html/ThinkPHP/ThinkPHP.php)