取mysql字段注释有关问题
取mysql字段注释问题
include("conn.php");
$query="select * from menu";
$result = mysql_query($query);
for($i=0;$i
$temp=mysql_field_name($result,$i);
echo $temp.":";
$query_1="select column_comment from INFORMATION_SCHEMA.Columns where table_name='admin' and table_schema='phpdata' and column_name like '$temp'";
$result_1=mysql_query($query_1);
$row_1=mysql_fetch_row($result_1);
echo $row_1[0]."
";
}
?>
这段代码在本地可以运行
但在服务器上只能取出字段名,不能取出注释
表名和库名没有写错。
请问是什么原因呢,会不会是要开通什么权限呢?
id:
Warning: mysql_fetch_row(): supplied argument is not a valid MySQL result resource in /www/users/swd888.com/1.php on line 11
------解决方案--------------------
你这句就运行失败了
$result_1=mysql_query($query_1);
把这个$query_1语句输出后,复制到数据库里运行一下
或是query后加个or die($mysql_error());看进一步的错误提示
------解决方案--------------------
密码错了?为啥被拒绝了,就没连上
忘了问,你数据库连接了没,怎么没有mysql_connect
------解决方案--------------------
没有权限访问 INFORMATION_SCHEMA 数据库吧。换用root用户试试。
------解决方案--------------------
检查一下你的conn.php函数,加上
- PHP code
if (!$con) { die('Could not connect: ' . mysql_error()); } <br><font color="#e78608">------解决方案--------------------</font><br>show full fields from table //这样试试 <br><font color="#e78608">------解决方案--------------------</font><br>$query_1 = "show full columns from phpdata from admin like '$temp'";<br>$result_1=mysql_query($query_1);<br>$row_1=mysql_fetch_row($result_1);<br>echo $row_1['Comment']."<br>";<br><br>试试看 <div class="clear"> </div>

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

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



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.

You can open phpMyAdmin through the following steps: 1. Log in to the website control panel; 2. Find and click the phpMyAdmin icon; 3. Enter MySQL credentials; 4. Click "Login".

Create a database using Navicat Premium: Connect to the database server and enter the connection parameters. Right-click on the server and select Create Database. Enter the name of the new database and the specified character set and collation. Connect to the new database and create the table in the Object Browser. Right-click on the table and select Insert Data to insert the data.

You can create a new MySQL connection in Navicat by following the steps: Open the application and select New Connection (Ctrl N). Select "MySQL" as the connection type. Enter the hostname/IP address, port, username, and password. (Optional) Configure advanced options. Save the connection and enter the connection name.

MySQL is an open source relational database management system, mainly used to store and retrieve data quickly and reliably. Its working principle includes client requests, query resolution, execution of queries and return results. Examples of usage include creating tables, inserting and querying data, and advanced features such as JOIN operations. Common errors involve SQL syntax, data types, and permissions, and optimization suggestions include the use of indexes, optimized queries, and partitioning of tables.

MySQL and SQL are essential skills for developers. 1.MySQL is an open source relational database management system, and SQL is the standard language used to manage and operate databases. 2.MySQL supports multiple storage engines through efficient data storage and retrieval functions, and SQL completes complex data operations through simple statements. 3. Examples of usage include basic queries and advanced queries, such as filtering and sorting by condition. 4. Common errors include syntax errors and performance issues, which can be optimized by checking SQL statements and using EXPLAIN commands. 5. Performance optimization techniques include using indexes, avoiding full table scanning, optimizing JOIN operations and improving code readability.

Redis uses a single threaded architecture to provide high performance, simplicity, and consistency. It utilizes I/O multiplexing, event loops, non-blocking I/O, and shared memory to improve concurrency, but with limitations of concurrency limitations, single point of failure, and unsuitable for write-intensive workloads.

Recovering deleted rows directly from the database is usually impossible unless there is a backup or transaction rollback mechanism. Key point: Transaction rollback: Execute ROLLBACK before the transaction is committed to recover data. Backup: Regular backup of the database can be used to quickly restore data. Database snapshot: You can create a read-only copy of the database and restore the data after the data is deleted accidentally. Use DELETE statement with caution: Check the conditions carefully to avoid accidentally deleting data. Use the WHERE clause: explicitly specify the data to be deleted. Use the test environment: Test before performing a DELETE operation.
