1. The scenario in which the problem occurs 1. Network delay, or use the FD tool to simulate requests sql select time form order where uid= 15 order by time desc limit 0 br > if (current time-time < 15) { exit (do not request frequently); } INS...
the company uses Aliyun s ECS server, which used to be a server (centos7) + a disk, and the environment and code were all put together. Once, when configuring the environment, the system file was deleted by mistake, so that the system could not boot. L...
Multi-table management, because the sum operation is used, so even if there is no data mybatis query will become one. The result is that null, if the default value is set on the sum, such as 0, it will return a piece of data that only the field sum is 0....
add printing function to react project as needed two solutions have been used 1. Embed react project with iframe 2, insert into react project through js print plug-in, mixed writing (there may be problems) I would like to ask which great god has ...
like this structure, click to switch tab style how to judge? html: <li v-for="(menu,n) in menus" :key="n""> <router-link :to="menu.sub? :menu.href" > {{menu.title}} data structure: .avtive { b...
it s too slow to mark hiragana with hiragana and use ruby tags by hand in Japanese like this. are there any ready-made modules, libraries and so on? Python looked around, but didn t find a suitable . Thank you! ...
scene I link to the database in three ways: first: use .connect () .end () . Continuous requests can be made for the first time, and then there will be ups and downs second: do not use .connect () .end () . Continuous requests. All request...
when scrapy crawls a picture of a web page, the class that inherits ImagesPipelines is customized in the pipelines file. but the custom pipelines cannot be executed after running the program. Item cannot pass the following is a custom pipelines clas...