如何阻止 MySQL 复制返回数组中的每一列条目？
我的 MySQL 查询返回包含重复条目的数组：编号键和标记键，其中包含相同的数据。这可能是标准的，但似乎很浪费，并且如果我打印值可能会导致问题。我的意思是，显然这不是一个大问题。但我只是好奇我是否能阻止它。看来没有必要。例如：
Array(
[0] => "Ted",
[first_name] => "Ted",
[1] => "Schmidlap",
[last_name] => "Schmidlap"
)
等等。
我对很多方面都很陌生，所以这可能是一个简单的问题，但谷歌搜索似乎没有给我任何答案。有谁知道发生这种情况的原因吗？我现在使用 PHP 的 PDO，但之前我直接通过 MySQL 函数进行操作，并且发生了同样的事情，所以我认为它是 MySQL 交互的副产品。
我可以迭代并取消设置数字，因为我不需要它们，但它们现在并不真正妨碍，所以这只是一个额外的步骤。不过，有没有一种方法可以让它们一开始就不被获取呢？
My MySQL queries are returning arrays with duplicate entries: numbered keys and labeled keys with the same data inside. This may be standard, but it seems like a waste, and something that could cause problems if I'm printing values. I mean, not a huge problem, obviously. But I'm just curious if I can stop that. It seems unnecessary. For example:
Array(
[0] => "Ted",
[first_name] => "Ted",
[1] => "Schmidlap",
[last_name] => "Schmidlap"
)
And so on.
I'm pretty new to a lot of this, so this may be a simple question, but Googling doesn't seem to have any answers for me. Anyone know the reason this happens? I'm using PHP's PDO now, but I was doing it straight through the MySQL functions before and the same thing was happening, so I assume it's a byproduct of MySQL interaction.
I can iterate through and unset the numeric ones, because I don't need them, but they're not really in the way right now, so that's just an extra step. Still, is there a way to simply not have them fetched in the first place?
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（4）
据推测，这种情况是在您使用 mysql_fetch_array （或类似的）之后发生的。
您需要添加一个标志来指定您想要返回的数组类型，或者 PHP 假定这两种类型。
即 mysql_fetch_array($result_set, MYSQL_ASSOC|MYSQL_NUM|MYSQL_BOTH)
Presumably this is happening after you use
mysql_fetch_array(or similar).You need to add in a flag to specify what array type you want returned or PHP assumes both.
i.e.
mysql_fetch_array($result_set, MYSQL_ASSOC|MYSQL_NUM|MYSQL_BOTH)这取决于您使用的功能。
有些函数返回两种类型，其他函数仅返回其中一种类型。
如果您使用
PDOStatement->fetch，请注意 它需要可选的$fetch_style参数。That depends on the function you are using.
Some functions return both types, others return only one of them.
If you are using
PDOStatement->fetch, notice the optional $fetch_style argument it takes.您的问题与
mysql_fetch_array函数有关。如果您只需要数字，请使用：
如果您只需要文本索引，请使用：
我通常使用 MySQLi，但对于 PDO，您可以在这里找到更多信息：https://www.php.net/manual/en/pdostatement.fetch.php
这似乎意味着您应该将其用于文本索引：
这用于数字索引：
Your issue is with the
mysql_fetch_arrayfunction.If you want only the numbers, use:
If you want only the text indexes, use:
I usually use MySQLi but for PDO you can find more information here: https://www.php.net/manual/en/pdostatement.fetch.php
Which seems to mean that you should be using this for text indexes:
And this for numeric indexes:
另外，请注意这一点，因为它没有在这里列出，如果您想要一个关联数组，您可以使用 mysql_fetch_assoc()，或者如果您想要一个枚举（编号）数组，请使用 mysql_fetch_row() 而不是 mysql_fetch_array()。我使用这个主要是因为没有它我经常会忘记标志，所以我养成了只使用特定函数的习惯。
Also, just to note this since it isn't listed here, if you want an associative array, you can use mysql_fetch_assoc(), or if you want an enumerated (numbered) array use mysql_fetch_row() instead of mysql_fetch_array(). I use this mostly because without it I would often forget the flag, so I got into the habit of just using the specific function.