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Label PostgreSQL , upsert , insert on conflict do background PostgreSQL 9.5 introduces a new feature, UPSERT(insert on conflict do), which returns directly when an insert encounters a constraint error, or performs UPDATE instead. The syntax is as follows Command: INSERT Description: create new rows in a table Syntax: [ WITH [ RE ...

Still and Video Media Capture Most of the content comes from AV Foundation Development Secret Book. AVFoundation capture class Capture session AVCaptureSession captures sessions that are equivalent to a virtual "plugboard" for connecting input and output resources. Capture session management data streams from physical devices ...

Spring security remembers my basic principles: When logged in, the request is sent to the filter Username Password Authentication Filter. When the filter is authenticated successfully, the RememberMeService is called and a token is generated, which is written to the browser cookie. At the same time, there is a TokenRepository inside the Rememb ...

This article is a hard summary for bloggers. I hope I can understand more deeply when I come back later. I also hope it can help beginners. Reproduced from: luogg's Blog Garden Thank you for your cooperation. optimization 1. Aliases (generally not used, easy to write to see the origin of the class) Previous wording: <insert id="insert"pa ...

EL expression ${EL expression} EL (Express Lanuage) expressions can be embedded in jsp pages to reduce the writing of jsp scripts. The purpose of EL is to replace the writing of scripts in jsp pages. Expression language Expressions Language, borrowing js, jquery grammar Effect: 1) Simplify the code in jsp, mainly to replace the JSP s ...

I. System Environment Operating System: CentOS 7 tomcat 8.0.47 Nginx 1.12.2 Redis 4.0.2 192.168.124.128 tomcat1+Nginx+Redis 192.168.124.130 tomcat2 Specific how to install these software, here is no longer introduced, please go online to find information. After installation, modify the port number of tomcat 2. If th ...

The original address is: JavaScript/jQuery, HTML and CSS to Build Web IM Remote and Timely Chat Communication Program This article is mainly for introduction. JavaScript and jQuery,HTML,CSS And using the third-party chat JavaScript (jsjac) framework to build a BS Web chat application. This program can communicate and send mes ...

Use and configuration of HTTPS on SL/TLS (IIS8 and iOS client) CA certificate 1. Domain Name Type SSL Certificate (DV SSL): The trust level is ordinary, only need to verify the authenticity of the website can issue certificates to protect the website; generally free. 2. Enterprise-type SSL Certificate (OV SSL): Strong trust level, ...

Sometimes we have to interact with WK WebView. Although WK WebView has high performance, there are still many pits. For example, we can get the js context in UIWebview in the following way, but WKWebView is error-prone let context = webView.valueForKeyPath("documentView.webView.mainFrame.javaScriptContext") as! JSContext context.evaluateScrip ...

hibernate comes with a simple logging framework. Here we introduce a powerful logging framework log4j. Baidu Encyclopedia's introduction to log4j is very good. Most of the content below is copied from Baidu Encyclopedia. Introduction to log4j (Baidu Encyclopedia) Log4j is Apache An open source project, using Log4j, we can control the destinat ...