mymysql与go-mysql-driver的一个区别 今天要写个工具就想顺便学下 go 。网上翻了下发现用比较多的是 mymysql 和 go-mysql-driver 。 ?? 这两个驱动网上比较的文章也有些了,不过都没有提到一个点,个人觉得是很重要的,记录一下。 ?? ?????? 先看使用 go-mysq
mymysql与go-mysql-driver的一个区别今天要写个工具就想顺便学下go。网上翻了下发现用比较多的是mymysql和go-mysql-driver。
??这两个驱动网上比较的文章也有些了,不过都没有提到一个点,个人觉得是很重要的,记录一下。
??
?????? 先看使用go-mysql-driver的例子。
?? db,_:=sql.Open("mysql",connect_string) ?? db.Query("set binlog_format=row") ? ?? rows,_:=db.Query("select @@binlog_format") ?? forrows.Next(){ ???? varvstring ???? rows.Scan(&v) ???? fmt.Println(v)? // 输出是MIXED (global值) ?? }?? ?? rows.Close() ?? db.Close() ? |
?从上面的输出可以看到,set语句无效。
原因是在database/sql这个库实现中, 上面的变量db维护的是一个线程池,而不是一个线程,因此前后两次执行db.Query并不保证在同一个session里面。
同样的, set @a=1,这种线程变量也是可能在后续的select中得不到1这个值。
?
?
由于mymysql 不是基于database/sql,以下代码能确保输出19
?
mydb := mysql.New("tcp", "", "ip:port”, user, password, dbname)
??? mydb.Connect()
??? mydb.Query("set @a=19")
??? res, _ := mydb.Start("select @a")
??? for {
????? row, _ := res.GetRow()
????? if row == nil {break}
????? fmt.Println(row.Str(0))
??? }??
???
??? mydb.Close()

InnoDBBufferPool reduces disk I/O by caching data and indexing pages, improving database performance. Its working principle includes: 1. Data reading: Read data from BufferPool; 2. Data writing: After modifying the data, write to BufferPool and refresh it to disk regularly; 3. Cache management: Use the LRU algorithm to manage cache pages; 4. Reading mechanism: Load adjacent data pages in advance. By sizing the BufferPool and using multiple instances, database performance can be optimized.

Compared with other programming languages, MySQL is mainly used to store and manage data, while other languages such as Python, Java, and C are used for logical processing and application development. MySQL is known for its high performance, scalability and cross-platform support, suitable for data management needs, while other languages have advantages in their respective fields such as data analytics, enterprise applications, and system programming.

MySQL is worth learning because it is a powerful open source database management system suitable for data storage, management and analysis. 1) MySQL is a relational database that uses SQL to operate data and is suitable for structured data management. 2) The SQL language is the key to interacting with MySQL and supports CRUD operations. 3) The working principle of MySQL includes client/server architecture, storage engine and query optimizer. 4) Basic usage includes creating databases and tables, and advanced usage involves joining tables using JOIN. 5) Common errors include syntax errors and permission issues, and debugging skills include checking syntax and using EXPLAIN commands. 6) Performance optimization involves the use of indexes, optimization of SQL statements and regular maintenance of databases.

MySQL is suitable for beginners to learn database skills. 1. Install MySQL server and client tools. 2. Understand basic SQL queries, such as SELECT. 3. Master data operations: create tables, insert, update, and delete data. 4. Learn advanced skills: subquery and window functions. 5. Debugging and optimization: Check syntax, use indexes, avoid SELECT*, and use LIMIT.

MySQL efficiently manages structured data through table structure and SQL query, and implements inter-table relationships through foreign keys. 1. Define the data format and type when creating a table. 2. Use foreign keys to establish relationships between tables. 3. Improve performance through indexing and query optimization. 4. Regularly backup and monitor databases to ensure data security and performance optimization.

MySQL is an open source relational database management system that is widely used in Web development. Its key features include: 1. Supports multiple storage engines, such as InnoDB and MyISAM, suitable for different scenarios; 2. Provides master-slave replication functions to facilitate load balancing and data backup; 3. Improve query efficiency through query optimization and index use.

SQL is used to interact with MySQL database to realize data addition, deletion, modification, inspection and database design. 1) SQL performs data operations through SELECT, INSERT, UPDATE, DELETE statements; 2) Use CREATE, ALTER, DROP statements for database design and management; 3) Complex queries and data analysis are implemented through SQL to improve business decision-making efficiency.

The basic operations of MySQL include creating databases, tables, and using SQL to perform CRUD operations on data. 1. Create a database: CREATEDATABASEmy_first_db; 2. Create a table: CREATETABLEbooks(idINTAUTO_INCREMENTPRIMARYKEY, titleVARCHAR(100)NOTNULL, authorVARCHAR(100)NOTNULL, published_yearINT); 3. Insert data: INSERTINTObooks(title, author, published_year)VA


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

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

SublimeText3 Chinese version
Chinese version, very easy to use