请问关于mysql返回数组的几个小问题
请教关于mysql返回数组的几个问题
1.mysql_fetch_array是不是性能比row,assoc差?
2.mysql_fetch_row 的输出方法只有$row[ num ]这种输出方法吗,那在没有数据表对照的情况下不是很麻烦吗?
3.现在我用的输出方法是while($row=mysql_fetch_array($result)){ $row['字段名'];}这样,有更优化的方法吗?
PDO网上没什么教学的文章,有本兄弟联的书也没怎么详细介绍
------解决思路----------------------
1、理论上是的，它返回带索引和关联的数据
2、你可以循环输出（当然你要知道每个索引和字段的对应关系）
3、都是这样取数据，你可以用mysql_fetch_assoc试试
------解决思路----------------------
看你需要的数据是什么，按需求获取。
mysql_fetch_row 会返回下标数组
mysql_fetch_assoc 会返回索引数组
mysql_fetch_array 会返回下标和索引数组
------解决思路----------------------
最初的 mysql 扩展只有
mysql_fetch_object 返回对象
mysql_fetch_array 返回数组，并通过第二个参数来决定范湖的是下标数组还是关联数组还是两者都有（默认）
mysql_fetch_row 和 mysql_fetch_assoc 时候来加入的，显然在书写上要高效一些
至于 mysql_fetch_row 的列顺序问题，根本就不是问题
本身 select 指令就应开列结果字段，仅用一个 * 是最低效的
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