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Arya's questions

Martin Hope
Arya
Asked: 2025-01-09 17:18:50 +0800 CST
  • 6

我有一个 JSONB 列，其中包含如下 JSON 数据

[
  {
    "url": "https://example.com",
    "vendor": "County"
  }
]

当我尝试使用“for update”进行查询时

select
    id,
    updated_at,
    jsonb_array_elements(data_src)->>'url' as vendor,
    in_use
from
    myschema.table a
where
    data_src @> '[{"vendor": "County"}]' limit 1 for update;

我收到以下错误

ERROR: FOR UPDATE is not allowed with set-returning functions in the target list

有没有办法解决这个问题？或者我需要修改 JSON 格式，这样jsonb_array_elements它就不会被使用了？

postgresql
Martin Hope
Arya
Asked: 2024-11-18 08:20:41 +0800 CST
  • 5

目前我正在使用 usaadress python 库来解析美国地址https://github.com/datamade/usaddress

示例代码

address = '456 Elm St, Someville, NY 54321'
print( usaddress.tag(address))

生成的结果是：

> ({'AddressNumber': '456', 'StreetName': 'Elm', 'StreetNamePostType':
> 'St', 'PlaceName': 'Someville', 'StateName': 'NY', 'ZipCode':
> '54321'}, 'Street Address')

除了“街道地址”之外，所有 JSON 值都有键，有没有办法为“街道地址”值分配一个键？这将使使用 GSON 或 Jackson 解析 JSON 变得更加简单

python
Martin Hope
Arya
Asked: 2024-11-10 02:13:16 +0800 CST
  • 6

我已经为我的应用实现了正常关机，并且正在进行测试以确保它按预期运行。控制台上显示的最后一条消息应该是“完成！”。然而事实并非如此。

@Service
public class MyClass {
    private boolean keepRunning = true;

    @Async
    public void myMethod(){

        do {
            try {
                System.out.println("Start");
                Thread.sleep(10000);
                System.out.println("Done!");
            }catch (Exception e){
                logger.error(e.getLocalizedMessage());
            }
        } while(keepRunning);
    }


    @PreDestroy
    void stop() {
        System.out.println("Shutdown called!");
        this.keepRunning = false;
    }
}

我还添加到了server.shutdown=graceful我的 application.properties 文件中

这是结束应用程序时控制台的完整输出

Start
2024-11-09T12:58:52.932-05:00  INFO 7374 --- [myapp] [ionShutdownHook] o.s.b.w.e.tomcat.GracefulShutdown        : Commencing graceful shutdown. Waiting for active requests to complete
2024-11-09T12:58:52.935-05:00  INFO 7374 --- [myapp] [tomcat-shutdown] o.s.b.w.e.tomcat.GracefulShutdown        : Graceful shutdown complete
Shutdown called!

Process finished with exit code 1

进程不是应该等待循环完成吗？如果不是，我是否可以等待循环完成然后再关闭应用程序？

编辑：

实现如下所示的自定义 taskExecutor 之后

@Bean(name = "test")
public ThreadPoolTaskExecutor taskExecutor() {
    ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
    executor.setCorePoolSize(1);
    executor.setMaxPoolSize(1);
    executor.setWaitForTasksToCompleteOnShutdown(true);
    executor.setThreadNamePrefix("test-");
    executor.initialize();
    return executor;
}

我还给它添加了“test-”的名称前缀，以确保该方法正在使用它。我还对方法进行了更改

@Async("test")
public void myMethod(){
    do {
        try {
            System.out.println("Start " + Thread.currentThread().getName());
            Thread.sleep(10000);
            System.out.println("Done!");
        }catch (Exception e){
            logger.error(e.getLocalizedMessage());
        }
    } while(keepRunning);
}

应用程序在打印“完成！”消息之前仍会结束。

Start test-1
2024-11-09T14:23:18.132-05:00  INFO 14449 --- [myapp] [ionShutdownHook] o.s.b.w.e.tomcat.GracefulShutdown        : Commencing graceful shutdown. Waiting for active requests to complete
2024-11-09T14:23:18.137-05:00  INFO 14449 --- [myapp] [tomcat-shutdown] o.s.b.w.e.tomcat.GracefulShutdown        : Graceful shutdown complete
Shutdown called!
spring