用php做一个查询语句的方法：1、创建一个php示例文件；2、使用mysqli_connect连接数据库；3、通过“$q = select * from user where gender = '.$gender.';$result = mysqli_query($db,$q);”语句实现查询即可。
本教程操作环境：windows7系统、php8.1版、dell g3电脑。
怎么用php做一个查询语句？
php使用select语句查询数据信息
<html><head> <title>finding user</title></head><body> <h2>finding users from mysql database.</h2> <form action="selectformhandler.php" method="post"> select gender: <select name="gender"> <option value="male">man</option> <option value="female">woman</option> </select><br /> <input name="submit" type="submit" value="find"/> </form></body></html>
<html><head> <title>user found</title></head><body> <h2>user found from mysql database.</h2><?php $gender = $_post['gender']; if(!$gender){ echo "error: there is no data passed."; exit; } if(!get_magic_quotes_gpc()){ $gender = addslashes($gender); } @ $db = mysqli_connect('localhost','root','12345678'); mysqli_select_db($db,'testphp'); if(mysqli_connect_errno()){ echo "error: could not connect to mysql database."; exit; } $q = "select * from user where gender = '".$gender."'"; $result = mysqli_query($db,$q); $rownum = mysqli_num_rows($result); for($i=0; $i<$rownum; $i++){ $row = mysqli_fetch_assoc($result); echo "id:".$row['id']."<br />"; echo "name:".$row['name']."<br />"; echo "age:".$row['age']."<br />"; echo "gender:".$row['gender']."<br />"; echo "info:".$row['info']."<br />"; } mysqli_free_result($result); mysqli_close($db);?></body></html>
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以上就是怎么用php做一个查询语句的详细内容。