Home Database Mysql Tutorial MySQL选择数据库use与mysql_select_db使用详解_MySQL

MySQL选择数据库use与mysql_select_db使用详解_MySQL

Jun 01, 2016 pm 01:17 PM
mysql database

 在mysql中如果我们在命令模式下选择与切换数据库直接使用use即可,在php中选择数据使用mysql_select_db即可,下面我来介绍一下。  

从命令提示符,选择MySQL数据库:

这是很简单的选择一个特定的数据库mysql>提示符。选择一个特定的数据库,可以使用SQL命令。

例子:
下面是一个例子,选择数据库称为 TUTORIALS:

 代码如下 复制代码

[root@host]# mysql -u root -p
Enter password:******
mysql> use TUTORIALS;
Database changed
mysql>

现在已经选择教程数据库教程数据库和所有的后续操作都将进行。

注: 所有的数据库名,表名,表中的字段名称是区分大小写的。所以将不得不使用prpoer名字,而给予任何SQL命令。

使用PHP脚本选择MySQL数据库

PHP提供了函数mysql_select_db选择一个数据库。成功返回TRUE,否则返回FALSE。

下面是这个例子展示如何选择一个数据库。

 代码如下 复制代码



Selecting MySQL Database - by www.111cn.net


$dbhost = 'localhost:3036';
$dbuser = 'guest';
$dbpass = 'guest123';
$conn = mysql_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
  die('Could not connect: ' . mysql_error());
}
echo 'Connected successfully';
mysql_select_db( 'TUTORIALS' );
mysql_close($conn);
?>

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