由于每个程序的特殊性,所以我在MYSQL的查询里使用了一些很通用的语句。用你的表名替换TABLE;用你的条件语句代替YOUR_CONDITION_HERE;用你希望按其排序的字段名代替WHATEVER(当然如果要排倒序,别忘了加上DESC子句)。
$qh=mysql_query("SELECT COUNT(*) AS rcnt FROM TABLE WHERE YOUR_CONDITION_HERE ORDER BY WHATEVER");
$data=mysql_fetch_array($qh);
$nr=$data["rcnt"];
//判断偏移量参数是否传递给了脚本,如果没有就使用默认值0
if (empty($offset))
{
$offset=0;
}
//查询结果(这里是每页20条,但你自己完全可以改变它)
$result=mysql_query("SELECT id,name,phone FROM TABLE WHERE YOUR_CONDITION_HERE ORDER BY WHATEVER LIMIT $offset, 20");
//显示返回的20条记录
while ($data=mysql_fetch_array($result))
{
//换成你用于显示返回记录的代码
}
//下一步,要写出到其它页面的链接
if(!$offset) //如果偏移量是0,不显示前一页的链接
{
$preoffset=$offset-20;
print "前一页 \n";
}
//计算总共需要的页数
$pages=ceil($nr/20); //$pages变量现在包含所需的页数
for ($i=1; $i <= $pages; $i++)
{
$newoffset=20*$i;
print "$i \n";
}
//检查是否是最后一页
if ($pages!=0 && ($newoffset/20)!=$pages)
{
print "下一页 \n";
}
?>
这只是向你大概地介绍了实现将查询结果分页显示的方法,其他的功能你自己完成。
注意两点:$PHP_SELF只有偏移量一个参数,你可以根据需要加入自己的东西;这种办法对包含百万条记录以上的表的查询效率不高。
phpbuiler.com

MySQL index cardinality has a significant impact on query performance: 1. High cardinality index can more effectively narrow the data range and improve query efficiency; 2. Low cardinality index may lead to full table scanning and reduce query performance; 3. In joint index, high cardinality sequences should be placed in front to optimize query.

The MySQL learning path includes basic knowledge, core concepts, usage examples, and optimization techniques. 1) Understand basic concepts such as tables, rows, columns, and SQL queries. 2) Learn the definition, working principles and advantages of MySQL. 3) Master basic CRUD operations and advanced usage, such as indexes and stored procedures. 4) Familiar with common error debugging and performance optimization suggestions, such as rational use of indexes and optimization queries. Through these steps, you will have a full grasp of the use and optimization of MySQL.

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