MongoCollection::remove

(PECL mongo >=0.9.0)

MongoCollection::remove — 从集合中删除记录

说明

public bool|array MongoCollection::remove ([ array $criteria = array() [, array $options = array() ]] )

参数

criteria

待删除记录的描述。

options

删除的选项。

"w"

See WriteConcerns. The default value for MongoClient is 1.
"justOne"

最多只删除一个匹配的记录。
"fsync"

Boolean, defaults to FALSE . Forces the insert to be synced to disk before returning success. If TRUE , an acknowledged insert is implied and will override setting w to 0.
"j"

Boolean, defaults to FALSE . Forces the write operation to block until it is synced to the journal on disk. If TRUE , an acknowledged write is implied and this option will override setting "w" to 0.

Note: If this option is used and journaling is disabled, MongoDB 2.6+ will raise an error and the write will fail; older server versions will simply ignore the option.
"w"

See WriteConcerns. The default value for MongoClient is 1.
"wtimeout"

Deprecated alias for "wTimeoutMS".
"safe"

Deprecated. Please use the WriteConcern w option.
"timeout"

Integer, defaults to MongoCursor::$timeout. If "safe" is set, this sets how long (in milliseconds) for the client to wait for a database response. If the database does not respond within the timeout period, a MongoCursorTimeoutException will be thrown.

返回值

如果设置了 "w" 选项，将会返回包含删除状态的 array。否则返回 TRUE 。

状态数组字段的解释位于 MongoCollection::insert() 的文档。

错误／异常

Throws MongoCursorException if the "w" option is set and the write fails.

Throws MongoCursorTimeoutException if the "w" option is set to a value greater than one and the operation takes longer than MongoCursor::$timeout milliseconds to complete. This does not kill the operation on the server, it is a client-side timeout. The operation in MongoCollection::$wtimeout is milliseconds.

更新日志

版本	说明
1.3.0	`options` 参数不再接受 boolean 值来代表 "justOne"。现在，必须使用 array('justOne' => true) 作为替代。
1.2.11	当 `options` 是 scalar 时产生一个 `E_DEPRECATED` 警告。
1.2.0	添加 "timeout" 选项。
1.0.11	在设置了 "safe" 之后，将在出现 "not master" 错误时断开连接。
1.0.9	添加了 "safe" 选项对 integer 的支持，之前只接受 boolean 值。添加了 "fsync" 选项。当使用了 "safe" 选项时将会返回包含错误信息的数组。否则和之前一样返回一个 boolean。
1.0.5	修改第二个参数为选项的 array。在 1.0.5 之前，第二个选项是 boolean 值，代表了 "safe" 选项。

范例

Example #1 MongoCollection::remove() 的 justOne 例子

  <?php

$radioactive  =  $db -> radioactive ;

 // 统计那有多少个钚
 $remaining  =  $radioactive -> count (array( 'type'  =>  94 ));

 $halflife  =  $remaining / 2 ;

 // 删除一半
 while ( $halflife  >  0 ) {
     $radioactive -> remove (array( 'type'  =>  94 ), array( "justOne"  =>  true ));
     $halflife --;
}

 ?>

参见

MongoCollection::insert() - 插入文档到集合中
MongoCollection::update() - Update records based on a given criteria
MongoDB » remove 的核心文档。

用户评论:

[#1] konstantin718 at gmail dot com [2013-01-21 03:17:08]

If you try to remove a document that doesn't exist, remove() won't throw an exception.

Even if 'w' is set to 1, remove() will return an array similar to this:

Array ( [n] => 0 [connectionId] => 10726 [err] => [ok] => 1 )

So, in order to see if a remove() was really successful, you need to look at [n] key. If it's 0, that means the remove() did not remove any documents.

If remove() is successful, [n] will be > 0.

[#2] David Winter [2010-01-02 05:55:09]

To remove a document based on its ID, you need to ensure that you pass the ID as a MongoID object rather than just a string:

<?php $id = '4b3f272c8ead0eb19d000000'; // will not work: $collection->remove(array('_id' => $id), true); // will work: $collection->remove(array('_id' => new MongoId($id)), true); ?>