sql 删除重复记录实现方法
"重复记录"有两个意义上的重复记录,一是完全重复的记录,也即所有字段均重复的记录,二是部分关键字段重复的记录,比如Name字段重复,而其他字段不一定重复或都重复可以忽略。

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Tomato Novel is a very popular novel reading software. We often have new novels and comics to read in Tomato Novel. Every novel and comic is very interesting. Many friends also want to write novels. Earn pocket money and edit the content of the novel you want to write into text. So how do we write the novel in it? My friends don’t know, so let’s go to this site together. Let’s take some time to look at an introduction to how to write a novel. Share the Tomato novel tutorial on how to write a novel. 1. First open the Tomato free novel app on your mobile phone and click on Personal Center - Writer Center. 2. Jump to the Tomato Writer Assistant page - click on Create a new book at the end of the novel.

HQL and SQL are compared in the Hibernate framework: HQL (1. Object-oriented syntax, 2. Database-independent queries, 3. Type safety), while SQL directly operates the database (1. Database-independent standards, 2. Complex executable queries and data manipulation).

Unfortunately, people often delete certain contacts accidentally for some reasons. WeChat is a widely used social software. To help users solve this problem, this article will introduce how to retrieve deleted contacts in a simple way. 1. Understand the WeChat contact deletion mechanism. This provides us with the possibility to retrieve deleted contacts. The contact deletion mechanism in WeChat removes them from the address book, but does not delete them completely. 2. Use WeChat’s built-in “Contact Book Recovery” function. WeChat provides “Contact Book Recovery” to save time and energy. Users can quickly retrieve previously deleted contacts through this function. 3. Enter the WeChat settings page and click the lower right corner, open the WeChat application "Me" and click the settings icon in the upper right corner to enter the settings page.

1. First of all, it is false to block and delete someone permanently and not add them permanently. If you want to add the other party after you have blocked them and deleted them, you only need the other party's consent. 2. If a user blocks someone, the other party will not be able to send messages to the user, view the user's circle of friends, or make calls with the user. 3. Blocking does not mean deleting the other party from the user's WeChat contact list. 4. If the user deletes the other party from the user's WeChat contact list after blocking them, there is no way to recover after deletion. 5. If the user wants to add the other party as a friend again, the other party needs to agree and add the user again.

Mobile games have become an integral part of people's lives with the development of technology. It has attracted the attention of many players with its cute dragon egg image and interesting hatching process, and one of the games that has attracted much attention is the mobile version of Dragon Egg. To help players better cultivate and grow their own dragons in the game, this article will introduce to you how to hatch dragon eggs in the mobile version. 1. Choose the appropriate type of dragon egg. Players need to carefully choose the type of dragon egg that they like and suit themselves, based on the different types of dragon egg attributes and abilities provided in the game. 2. Upgrade the level of the incubation machine. Players need to improve the level of the incubation machine by completing tasks and collecting props. The level of the incubation machine determines the hatching speed and hatching success rate. 3. Collect the resources required for hatching. Players need to be in the game

1. Open the Douyin app, click [Message] at the bottom of the interface, and click the chat conversation entry that needs to be deleted. 2. Long press any chat record, click [Multiple Select], and check the chat records you want to delete. 3. Click the [Delete] button in the lower right corner and select [Confirm deletion] in the pop-up window to permanently delete these records.

Setting font size has become an important personalization requirement as mobile phones become an important tool in people's daily lives. In order to meet the needs of different users, this article will introduce how to improve the mobile phone use experience and adjust the font size of the mobile phone through simple operations. Why do you need to adjust the font size of your mobile phone - Adjusting the font size can make the text clearer and easier to read - Suitable for the reading needs of users of different ages - Convenient for users with poor vision to use the font size setting function of the mobile phone system - How to enter the system settings interface - In Find and enter the "Display" option in the settings interface - find the "Font Size" option and adjust it. Adjust the font size with a third-party application - download and install an application that supports font size adjustment - open the application and enter the relevant settings interface - according to the individual

The difference between Go language methods and functions lies in their association with structures: methods are associated with structures and are used to operate structure data or methods; functions are independent of types and are used to perform general operations.
