mongodb index array

First, the index introductionIn MongoDB, indexes are used to support efficient queries. If there is no index, MONGODB must scan each document in the entire collection to find a matching document. However, if an appropriate index is established,

Indexes can often greatly improve the efficiency of queries, and if there is no index, MongoDB must scan every file in the collection and select those records that meet the query criteria when reading the data. This scan full set of query efficiency

_ Id Index An index is automatically created for the _ id field for all sets except the set of capacity. This is a special index and cannot be deleted. The _ id index forces that its keywords are unique (except for some scenarios in the partition

Previous wordsIndexes can often greatly improve the efficiency of queries, and if there is no index, MongoDB must scan every file in the collection and select those records that meet the query criteria when reading the data. This scan full set of

MongoDB cluster building (master-slave replication, replica and) (5), mongodb master-slaveVi. Architecture ManagementMongodb master-slave clusters are divided into two types:1: master-Slave replication (master-Slave) -- The Slave server will not

MongoDB data model and index learning summary, mongodb ModelMongoDB data model and index learning Summary 1. MongoDB Data Model: MongoDB data storage structure:MongoDB uses BSON (binary json, binary encoding) data format for document (large files

First, IntroductionIndexing in MongoDB can improve query efficiency, only need to scan the index only a small portion of this collection, and only to load this small part into memory, the efficiency greatly improved, if not indexed, in the query,

/*** MongoDB $type operator*/ /*** The $type operator is based on the Bson type to retrieve the matching data type in the collection and returns the result.* The types of MongoDB that can be used are shown in the following table:* Type Number Notes*

The blog has moved Https://www.tianmingxing.com MongoDB is an open-source, document-oriented NoSQL (not only SQL) database written using C + +, and one of the most popular NoSQL databases. NoSQL Introduction NoSQL means "Not just SQL", is the

Index typeMONGDB indexes are divided into the following types: Single-key index, composite index, geospatial Index, full-text index, and hash indexSingle-key index (single Field Indexes)An index created on a key is a single-key index, which is the