问题描述
有时会出现奇怪的重复键错误
duplicate key value violates unique constraint "session_pkey"
Key (workplace)=(WIN-N9BSKUNKBC8 ) already exists.
发生在脚本中:
delete from session where workplace='WIN-N9BSKUNKBC8' ;
INSERT INTO session (workplace,ipaddress,logintime,loggeduser)
SELECT 'WIN-N9BSKUNKBC8',inet_client_addr()::CHAR(14),current_timestamp::CHAR(28),CURRENT_USER WHERE NOT EXISTS (SELECT 1 FROM session WHERE workplace='WIN-N9BSKUNKBC8' )
Sript 每 10 分钟运行一次窗体 Windows 任务调度程序。错误只是偶尔发生。
如何解决这个问题? 表定义为
CREATE TABLE public.session
(
loggeduser character(10),workplace character(16) NOT NULL,ipaddress character(20),logintime character(28),activity timestamp with time zone,CONSTRAINT session_pkey PRIMARY KEY (workplace)
)
环境:
Postgresql 13.1,compiled by Visual C++ build 1914,64-bit
Windows server 2019
psqlODBC driver 13.00.0000
解决方法
您可以使用on conflict
:
INSERT INTO session (workplace,ipaddress,logintime,loggeduser)
SELECT 'WIN-N9BSKUNKBC8',inet_client_addr()::CHAR(14),current_timestamp::CHAR(28),CURRENT_USER
ON CONFLICT DO NOTHING;
鉴于您只有一行进入,我猜测问题是由于并发问题。