略微加速

PHP官方手册 - 互联网笔记

PHP - Manual: MongoCollection::createIndex

2024-12-25

MongoCollection::createIndex

(PECL mongo >=1.5.0)

MongoCollection::createIndex — Creates an index on the specified field(s) if it does not already exist

说明

public MongoCollection::createIndex ( array $keys [, array $options = array() ] ) : bool

Creates an index on the specified field(s) if it does not already exist. Fields may be indexed with a direction (e.g. ascending or descending) or a special type (e.g. text, geospatial, hashed).

Note:

This method will use the » createIndexes database command when communicating with MongoDB 2.6+. For previous database versions, the method will perform an insert operation on the special system.indexes collection.

参数

keys

An array specifying the index's fields as its keys. For each field, the value is either the index direction or » index type. If specifying direction, specify 1 for ascending or -1 for descending.

options

An array of options for the index creation. We pass all given options straight to the server, but a non-exhaustive list of currently available options include:

  • "unique"

    Specify TRUE to create a unique index. The default value is FALSE. This option applies only to ascending/descending indexes.

    Note:

    When MongoDB indexes a field, if a document does not have a value for the field, a NULL value is indexed. If multiple documents do not contain a field, a unique index will reject all but the first of those documents. The "sparse" option may be used to overcome this, since it will prevent documents without the field from being indexed.

  • "sparse"

    Specify TRUE to create a sparse index, which only indexes documents containing a specified field. The default value is FALSE.

  • "expireAfterSeconds"

    The value of this option should specify the number of seconds after which a document should be considered expired and automatically removed from the collection. This option is only compatible with single-field indexes where the field will contain MongoDate values.

    Note:

    This feature is available in MongoDB 2.2+. See » Expire Data from Collections by Setting TTL for more information.

  • "name"

    A optional name that uniquely identifies the index.

    Note:

    By default, the driver will generate an index name based on the index's field(s) and ordering or type. For example, a compound index array("x" => 1, "y" => -1) would be named "x_1_y_-1" and a geospatial index array("loc" => "2dsphere") would be named "loc_2dsphere". For indexes with many fields, it is possible that the generated name might exceed MongoDB's » limit for index names. The "name" option may be used in that case to supply a shorter name.

  • "background"

    Builds the index in the background so that building an index does not block other database activities. Specify TRUE to build in the background. The default value is FALSE.

    Warning

    Prior to MongoDB 2.6.0, index builds on secondaries were executed as foreground operations, irrespective of this option. See » Building Indexes with Replica Sets for more information.

  • "socketTimeoutMS"

    This option specifies the time limit, in milliseconds, for socket communication. If the server does not respond within the timeout period, a MongoCursorTimeoutException will be thrown and there will be no way to determine if the server actually handled the write or not. A value of -1 may be specified to block indefinitely. The default value for MongoClient is 30000 (30 seconds).

The following option may be used with MongoDB 2.6+:

  • "maxTimeMS"

    Specifies a cumulative time limit in milliseconds for processing the operation on the server (does not include idle time). If the operation is not completed by the server within the timeout period, a MongoExecutionTimeoutException will be thrown.

The following options may be used with MongoDB versions before 2.8:

  • "dropDups"

    Specify TRUE to force creation of a unique index where the collection may contain duplicate values for a key. MongoDB will index the first occurrence of a key and delete all subsequent documents from the collection that contain a duplicate value for that key. The default value is FALSE.

    Warning

    "dropDups" may delete data from your database. Use with extreme caution.

    Note:

    This option is not supported on MongoDB 2.8+. Index creation will fail if the collection contains duplicate values.

The following options may be used with MongoDB versions before 2.6:

  • "w"

    See WriteConcerns. The default value for MongoClient is 1.

  • "wTimeoutMS"

    This option specifies the time limit, in milliseconds, for write concern acknowledgement. It is only applicable when "w" is greater than 1, as the timeout pertains to replication. If the write concern is not satisfied within the time limit, a MongoCursorException will be thrown. A value of 0 may be specified to block indefinitely. The default value for MongoClient is 10000 (ten seconds).

The following options are deprecated and should no longer be used:

  • "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.

  • "wtimeout"

    Deprecated alias for "wTimeoutMS".

返回值

Returns an array containing the status of the index creation. The array contains whether the operation succeeded ("ok"), the number of indexes before and after the operation ("numIndexesBefore" and "numIndexesAfter"), and whether the collection that the index belongs to has been created ("createdCollectionAutomatically"). If the index already existed and did not need to be created, a "note" field may be present in lieu of "numIndexesAfter".

With MongoDB 2.4 and earlier, a status document is only returned if the write concern is at least 1. Otherwise, TRUE is returned. The fields in the status document are different, except for the "ok" field, which signals whether the index creation was successful. Additional fields are described in the documentation for MongoCollection::insert().

错误／异常

Throws MongoException if the index name is longer than 128 bytes, or if the index specification is not an array.

Throws MongoDuplicateKeyException if the server could not create the unique index due to conflicting documents.

Throws MongoResultException if the server could not create the index due to an error.

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.

范例

Example #1 MongoCollection::createIndex() example

<?php

$c = new MongoCollection($db, 'foo');

// create an index on 'x' ascending
$c->createIndex(array('x' => 1));

// create a unique index on 'y'
$c->createIndex(array('y' => 1), array('unique' => true));

// create a compound index on 'za' ascending and 'zb' descending
$c->createIndex(array('za' => 1, 'zb' => -1));

?>

Example #2 Geospatial Indexing

Mongo supports geospatial indexes, which allow you to search for documents near a given location or within a shape. The following example creates a geospatial index on the "loc" field:

<?php

$collection->createIndex(array('loc' => '2dsphere'));

?>

Example #3 Drop duplicates example

<?php

$collection->insert(array('username' => 'joeschmoe'));
$collection->insert(array('username' => 'joeschmoe'));

/* Index creation fails, since you cannot create a unique index on a field when
 * duplicates exist.
 */
$collection->createIndex(array('username' => 1), array('unique' => 1));

/* MongoDB will one of the conflicting documents and allow the unique index to
 * be created.
 */
$collection->createIndex(array('username' => 1), array('unique' => 1, 'dropDups' => 1));

/* We now have a unique index and subsequent inserts with the same username will
 * fail.
 */
$collection->insert(array('username' => 'joeschmoe'));

?>

参见

add a note add a note

User Contributed Notes 2 notes

up
4
bosuy dot misha at gmail dot com
2 years ago
Create index using MongoDB\Driver

$query = new \MongoDB\Driver\Query(['createIndex' => ['my_column' => 1]], []);
$manager = new \MongoDB\Driver\Manager($mongo_connection)
$manager->executeQuery('my_db.my_collection', $query);
up
0
sNICkers
2 years ago
For PHP 7.x
Create index using MongoDB\Driver

$command = new \MongoDB\Driver\Command([
    'createIndexes' => 'my_collection_name',
    'indexes' => [[
        'name' => 'my_index_name',
        'key'  => ['my_field_name' => 1]
    ]]
]);

$instance = new \MongoDB\Driver\Manager('mongodb://127.0.0.1:27017');
$instance->executeCommand('my_db_name', $command);
add a note add a note

官方地址：https://www.php.net/manual/en/mongocollection.createindex.php

有任何技术问题请点击这里 网站运营推广招聘
IT PHP 编程语言 Linux 开发编程 科技 Elasticsearch HTML/CSS/XML 网络 数据库 JAVA 面试 NoSQL C/C++ Golang Git 算法 操作系统 正则表达式 Redis 互联网 MySql JavaScript 运维 软件 国际 架构设计 Mac OS TCP/IP Excel Vim Windows Socket Oracle VR MongoDB Python 运营 MemCache 商业 硬件 电子 娱乐 设计 nginx 摄影 游戏 WordPress HTTP 团建 数码电器
冷却塔厂家 广告
中文GPT4.0无需注册 广告
php7 安装fileinfo扩展 preg_split — 通过一个正则表达式分隔字符串 php位值,解决 PHP 中 usort 在值相同时改变原始位置的问题 [PHP] inet_pton/inet_ntop IP地址转换函数 PHP 8.1 [鸟哥]PHP_INT_MIN 和 -9223372036854775808 ADORecordSet对象 adodb手册 opcache预加载 Composer的Packagist资源 array_multisort() 多字段排序 mysql面试题 PHP json解析（json_decode）页面工具 php中几种注释规范 PHPMailer设置utf8 PHPMailer字符集CharSet php扩展开发 [原创]诡异的php-fpm超时问题 PHP mkdir()写出来的权限与mode值不符合 PHP5 扩展SOAP 调用 webservice php上周一、本周一、下周一日期
联系我们 半月雨文化 可降解耗材网 蓝云环保 78免费小説 上海网站seo优化 工程造价 币安app官网下载 币安app官网下载安卓 币安app官网下载 seo查询
北京半月雨文化科技有限公司.版权所有 京ICP备12026184号-3