Home Backend Development PHP Problem How does php determine whether the mysql query result is empty?

How does php determine whether the mysql query result is empty?

Jul 23, 2021 am 09:15 AM
mysql php

php method to determine whether the mysql query result is empty: 1. Query through the "if (mysql_num_rows($rows) < 1){...}" method; 2. Query through "if(!mysql_affected_rows( )){...}" method query.

How does php determine whether the mysql query result is empty?

The operating environment of this article: windows7 system, PHP7.1 version, DELL G3 computer

How does php determine whether the mysql query result is null?

php determines whether the query result of the SQL statement is empty

determines whether the result set of the SQL statement query is empty!

<?php
//方法一 获取select结果集的行数
$rows=mysql_query("select * from `student` where `age`=&#39;16&#39;;");
if (mysql_num_rows($rows) < 1){
echo &#39;查询无数据!&#39;;
}
//方法二 返回上一次操作受影响的行数
$rows=mysql_query("select * from `student` where `age`=&#39;16&#39;;");
if(!mysql_affected_rows()){
    echo &#39;查询无数据!&#39;;
}
?>
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