Table of Contents
Reply content:
Home Backend Development PHP Tutorial Why can't mysql be written like this using update?

Why can't mysql be written like this using update?

Aug 04, 2016 am 09:20 AM
mysql php

Write like this

if(!mysql_query("update kxwr (name,sex,old) values ​​('Xiaoming','male','18') where id='1'")){
exit('Modification failed');
}
echo'The modification was successful! ';

Why does it return failure?

If

if(!mysql_query("insert into kxwr (name,sex,old,id) values ​​('Xiaoming','male','18','1')")) {
exit('Add failed');
}
echo'Added successfully! ';

In this way, insert can be successful but update cannot. Why?

Reply content:

Write like this

if(!mysql_query("update kxwr (name,sex,old) values ​​('Xiaoming','male','18') where id='1'")){
exit('Modification failed');
}
echo'The modification was successful! ';

Why does it return failure?

If

if(!mysql_query("insert into kxwr (name,sex,old,id) values ​​('Xiaoming','male','18','1')")) {
exit('Add failed');
}
echo'Added successfully! ';

In this way, insert can be successful but update cannot. Why?

Wrong grammar

<code>$sql=" UPDATE kxwr SET name='小明' sex ='男' old ='11' WHERE id='1' ";</code>
Copy after login

Grammar issues. update table_name set column1=xxx where column2=yyy;This is right

Learn sql first.

update is not used like that

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Best Graphic Settings
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. How to Fix Audio if You Can't Hear Anyone
3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

mysql whether to change table lock table mysql whether to change table lock table Apr 08, 2025 pm 05:06 PM

When MySQL modifys table structure, metadata locks are usually used, which may cause the table to be locked. To reduce the impact of locks, the following measures can be taken: 1. Keep tables available with online DDL; 2. Perform complex modifications in batches; 3. Operate during small or off-peak periods; 4. Use PT-OSC tools to achieve finer control.

Unable to log in to mysql as root Unable to log in to mysql as root Apr 08, 2025 pm 04:54 PM

The main reasons why you cannot log in to MySQL as root are permission problems, configuration file errors, password inconsistent, socket file problems, or firewall interception. The solution includes: check whether the bind-address parameter in the configuration file is configured correctly. Check whether the root user permissions have been modified or deleted and reset. Verify that the password is accurate, including case and special characters. Check socket file permission settings and paths. Check that the firewall blocks connections to the MySQL server.

RDS MySQL integration with Redshift zero ETL RDS MySQL integration with Redshift zero ETL Apr 08, 2025 pm 07:06 PM

Data Integration Simplification: AmazonRDSMySQL and Redshift's zero ETL integration Efficient data integration is at the heart of a data-driven organization. Traditional ETL (extract, convert, load) processes are complex and time-consuming, especially when integrating databases (such as AmazonRDSMySQL) with data warehouses (such as Redshift). However, AWS provides zero ETL integration solutions that have completely changed this situation, providing a simplified, near-real-time solution for data migration from RDSMySQL to Redshift. This article will dive into RDSMySQL zero ETL integration with Redshift, explaining how it works and the advantages it brings to data engineers and developers.

Can mysql handle multiple connections Can mysql handle multiple connections Apr 08, 2025 pm 03:51 PM

MySQL can handle multiple concurrent connections and use multi-threading/multi-processing to assign independent execution environments to each client request to ensure that they are not disturbed. However, the number of concurrent connections is affected by system resources, MySQL configuration, query performance, storage engine and network environment. Optimization requires consideration of many factors such as code level (writing efficient SQL), configuration level (adjusting max_connections), hardware level (improving server configuration).

Query optimization in MySQL is essential for improving database performance, especially when dealing with large data sets Query optimization in MySQL is essential for improving database performance, especially when dealing with large data sets Apr 08, 2025 pm 07:12 PM

1. Use the correct index to speed up data retrieval by reducing the amount of data scanned select*frommployeeswherelast_name='smith'; if you look up a column of a table multiple times, create an index for that column. If you or your app needs data from multiple columns according to the criteria, create a composite index 2. Avoid select * only those required columns, if you select all unwanted columns, this will only consume more server memory and cause the server to slow down at high load or frequency times For example, your table contains columns such as created_at and updated_at and timestamps, and then avoid selecting * because they do not require inefficient query se

MySQL: The Ease of Data Management for Beginners MySQL: The Ease of Data Management for Beginners Apr 09, 2025 am 12:07 AM

MySQL is suitable for beginners because it is simple to install, powerful and easy to manage data. 1. Simple installation and configuration, suitable for a variety of operating systems. 2. Support basic operations such as creating databases and tables, inserting, querying, updating and deleting data. 3. Provide advanced functions such as JOIN operations and subqueries. 4. Performance can be improved through indexing, query optimization and table partitioning. 5. Support backup, recovery and security measures to ensure data security and consistency.

Can mysql run on android Can mysql run on android Apr 08, 2025 pm 05:03 PM

MySQL cannot run directly on Android, but it can be implemented indirectly by using the following methods: using the lightweight database SQLite, which is built on the Android system, does not require a separate server, and has a small resource usage, which is very suitable for mobile device applications. Remotely connect to the MySQL server and connect to the MySQL database on the remote server through the network for data reading and writing, but there are disadvantages such as strong network dependencies, security issues and server costs.

The relationship between mysql user and database The relationship between mysql user and database Apr 08, 2025 pm 07:15 PM

In MySQL database, the relationship between the user and the database is defined by permissions and tables. The user has a username and password to access the database. Permissions are granted through the GRANT command, while the table is created by the CREATE TABLE command. To establish a relationship between a user and a database, you need to create a database, create a user, and then grant permissions.

See all articles