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1, Requirement description 1. The data from the front end is stored in the database, which needs to be escaped after the background When the user fills in the data, sometimes some html special characters (such as trademark symbol) will be passed in. At this time, we need to escape the special characters from the front end, an ...

1. Database table initialization Table mygoods is the commodity table, cat_id is the classification ID, goods_id is the commodity ID, and status is the current status bit of the commodity (1: valid, 0: invalid). The table creation statement is as follows: CREATE TABLE `mygoods` ( `goods_id` int(11) unsigned NOT NULL AUTO_IN ...

Getting started with mysql 01 What is a database? Classification of database The construction of mysql database mysql introduction Installation software Initialization View initial password Login with initial password & & modify initial password Modify password policy Related parameters ...

The 8.0 version of mysql adds the functions related to password policy management. The new version can do more control and operation on account password requirements, such as setting reusable restrictions on passwords, modifying password verification policies, etc. the security has been improved compared with the 5.7 version. Let's look at i ...

General Mapper notes Build development environment (spring boot) Database tableImport dependency <dependency> <groupId>tk.mybatis</groupId> <artifactId>mapper</artifactId> <version>4.0.4</version> </dependency> To configure server: port: ...

Just about to leave work, I was stopped by a development colleague. Let's see a strange problem: the query method of the same Mapper interface of Mybatis, the first return result is different from the second return result. I can't think about it! problem Talk is heap. Show me the code mapper interface definition public interface GoodsTrackMap ...

introduce Last week, I was confronted with a colleague about an interface. My front-end colleague asked me if I had written the interface document incorrectly, how many exception tags are on an order, and should I not return an array?Why only one number was returned. Because this interface is a call to other micro services, I am also confused. ...

1. Execution of getById Previous As mentioned, when Mapper.java is created, it is created as a jdk proxy and the proxy processing class is MapperProxy. So when the getById method of UserMapper is executed, the invoke method is executed in MapperProxy. //MapperProxy.java @Override public Object invoke(Object proxy, Method method, Object[ ...

This blog is a reading note of "data analysis by Python". Please do not reprint it for other business purposes. Article directory 1. Hierarchical index 1.1 reorder and hierarchy 1.2 summary statistics by level 2. Join and merge datasets 2.1 database style DataFrame connection 2.2 merge by ...

1. Classification of database languages DDL: Database Definition Language Used to create, modify, and delete data structures within a database, such as: 1: Create and delete databases (CREATE DATABASE || DROP DATABASE); 2: Create, modify, rename, delete tables (CREATE TABLE | ALTER TABLE | RENAME TABLE | DROP TABLE, TRUNCATE TABLE); 3: Create a ...