数据库管理系统
今天总结了一下《数据库》,画了两个图,下面就根据我的图,说下学习的知识。 图 1 数据库设计好了就应该开始使用了,这时就应该编制并调试相应的应用程序了,之后进行少部分数据入库,开始数据库的试运行。主要是进行性能和功能的调试。当然维护是必不可少
今天总结了一下《数据库》,画了两个图,下面就根据我的图,说下学习的知识。
图 1
数据库设计好了就应该开始使用了,这时就应该编制并调试相应的应用程序了,之后进行少部分数据入库,开始数据库的试运行。主要是进行性能和功能的调试。当然维护是必不可少的。数据的安全性我们应该都考虑到。
下面说下图2,图2的大角色就是DBS(数据库系统)了,它包括DBA(数据库管理员),DBMS(软件),DB(数据库)。应用程序通过DBMS去接触DB中的数据,然后DB再通过DBMS将查询结果进行处理反馈给应用程序。DBMS中含有DDL的编译程序(定义数据库的三级两层),DML的编译程序或解释程序(增、删、改、查),还有存放三级结构定义的数据字典-DD。DBS运行时,DBMS要对其进行监控。DBS运行的最小逻辑单位是“事务”,对数据库的操作都要以事务为单位来执行或撤销。DBA通过DBMS中的某些程序和DD系统来掌握整个DBS的工作情况。所以DBA的责任是相当重的,需要水平高、资历深的人担任。
这就是我对本书的理解,不足之处还请多多指教!

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics











Apple's latest releases of iOS18, iPadOS18 and macOS Sequoia systems have added an important feature to the Photos application, designed to help users easily recover photos and videos lost or damaged due to various reasons. The new feature introduces an album called "Recovered" in the Tools section of the Photos app that will automatically appear when a user has pictures or videos on their device that are not part of their photo library. The emergence of the "Recovered" album provides a solution for photos and videos lost due to database corruption, the camera application not saving to the photo library correctly, or a third-party application managing the photo library. Users only need a few simple steps

Hibernate polymorphic mapping can map inherited classes to the database and provides the following mapping types: joined-subclass: Create a separate table for the subclass, including all columns of the parent class. table-per-class: Create a separate table for subclasses, containing only subclass-specific columns. union-subclass: similar to joined-subclass, but the parent class table unions all subclass columns.

To handle database connection errors in PHP, you can use the following steps: Use mysqli_connect_errno() to obtain the error code. Use mysqli_connect_error() to get the error message. By capturing and logging these error messages, database connection issues can be easily identified and resolved, ensuring the smooth running of your application.

How to use MySQLi to establish a database connection in PHP: Include MySQLi extension (require_once) Create connection function (functionconnect_to_db) Call connection function ($conn=connect_to_db()) Execute query ($result=$conn->query()) Close connection ( $conn->close())

JSON data can be saved into a MySQL database by using the gjson library or the json.Unmarshal function. The gjson library provides convenience methods to parse JSON fields, and the json.Unmarshal function requires a target type pointer to unmarshal JSON data. Both methods require preparing SQL statements and performing insert operations to persist the data into the database.

Using the database callback function in Golang can achieve: executing custom code after the specified database operation is completed. Add custom behavior through separate functions without writing additional code. Callback functions are available for insert, update, delete, and query operations. You must use the sql.Exec, sql.QueryRow, or sql.Query function to use the callback function.

MySQL is an open source relational database management system. 1) Create database and tables: Use the CREATEDATABASE and CREATETABLE commands. 2) Basic operations: INSERT, UPDATE, DELETE and SELECT. 3) Advanced operations: JOIN, subquery and transaction processing. 4) Debugging skills: Check syntax, data type and permissions. 5) Optimization suggestions: Use indexes, avoid SELECT* and use transactions.

Through the Go standard library database/sql package, you can connect to remote databases such as MySQL, PostgreSQL or SQLite: create a connection string containing database connection information. Use the sql.Open() function to open a database connection. Perform database operations such as SQL queries and insert operations. Use defer to close the database connection to release resources.
