Example of how to randomly pick mysql records in php_PHP tutorial

To randomly select mysql records in php, we can directly use mysql_query to execute the data obtained by the select rand function in mysql and read it out. Let me introduce you to a specific example.

Method 1:

The code is as follows

代码如下	复制代码
select * from tablename order by rand() limit 1

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select * from tablename order by rand() limit 1

代码如下	复制代码
$query= "SELECT count(*) as count FROM recommends"; .... $max_num = $row['count']; // 取记录总数 srand((double)microtime()*1000000); // 随机数种子 $se_pos = rand(0, $max_num); // 随机数范围 $length = 6; // 记录条数 if (($max_num - $se_pos) <= $length) {     $se_pos = $max_num - $se_pos; // 记录数不足6条的情况 } $query = "SELECT * FROM recommendsn limit ".$se_pos.",".$length;

Change the value after limit to the number of records you want to randomly select. Only one is taken here.

Method 2:

$query= "SELECT count(*) as count FROM recommends"; ....

The code is as follows

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代码如下

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$db = mysql_connect("localhost", "root"); mysql_select_db("xyj",$db); $result=mysql_query("SELECT * FROM obj",$db); $max_num=mysql_num_rows($result);//取得数据库的记录数 srand((double)microtime()*10000000); //生成随机数种子。 $se_pos=rand(0, $max_num-1); //从0到最大记录数取随机数 $length=30; //设定共取多少条记录 //下面是取出指定数目的记录。 $result_lim=mysql_query("select * from obj limit $se_pos,$length",$db); $myrow_lim=mysql_fetch_array($result_lim); printf("%sn", $se_pos);//显示随机得到的记录号 printf("%sn", $myrow_lim["name"]);//显示随机得到的记录的name字段

$max_num = $row['count']; // Get the total number of records srand((double)microtime()*1000000); // Random number seed

$se_pos = rand(0, $max_num); //Random number range

$length = 6; //Number of records if (($max_num - $se_pos) <= $length) { $se_pos = $max_num - $se_pos; // When the number of records is less than 6 } $query = "SELECT * FROM recommendsn limit ".$se_pos.",".$length; Example 3

Suppose there is a database named xyj. There is a table obj in the database. There is a field in the table called name. Now we want to randomly select a record from the table. The specific procedure is as follows:

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