[摘要]+-------------+-----------------+----------------+2 rows in set (0.01 sec)mysql>在PHP脚本中使用JOINPHP...
+-------------+-----------------+----------------+2 rows in set (0.01 sec)mysql>
在PHP脚本中使用JOIN
PHP 中使用mysql_query()函数来执行SQL语句,你可以使用以上的相同的SQL语句作为mysql_query()函数的参数。
尝试如下实例:
<?php$dbhost = 'localhost:3036';$dbuser = 'root';$dbpass = 'rootpassword';$conn = mysql_connect($dbhost, $dbuser, $dbpass);if(! $conn ){ die('Could not connect: ' . mysql_error());}$sql = 'SELECT a.tutorial_id, a.tutorial_author, b.tutorial_count FROM tutorials_tbl a, tcount_tbl b WHERE a.tutorial_author = b.tutorial_author';mysql_select_db('TUTORIALS');$retval = mysql_query( $sql, $conn );if(! $retval ){ die('Could not get data: ' . mysql_error());}while($row = mysql_fetch_array($retval, MYSQL_ASSOC)){ echo "Author:{$row['tutorial_author']} <br> ". "Count: {$row['tutorial_count']} <br> ". "Tutorial ID: {$row['tutorial_id']} <br> ". "--------------------------------<br>";} echo "Fetched data successfully\n";mysql_close($conn);?>MySQL LEFT JOIN
MySQL left join 与 join 有所不同。 MySQL LEFT JOIN 会读取左边数据表的全部数据,即便右边表无对应数据。
实例
尝试以下实例,理解MySQL LEFT JOIN的应用:
root@host# mysql -u root -p password;Enter password:*******mysql> use TUTORIALS;Database changedmysql> SELECT a.tutorial_id, a.tutorial_author, b.tutorial_count -> FROM tutorials_tbl a LEFT JOIN tcount_tbl b -> ON a.tutorial_author = b.tutorial_author;+-------------+-----------------+----------------+
关键词:Mysql Join的运用图文详细教程