mongodb find projection example

Original link http://www.cnblogs.com/zhangzili/p/4975080.htmlMongoDB knowledge points at a glance1. Start the MongoDB database:Go to the MongoDB installation directory and execute the following commandC:\Program

MongoDB projection means to select only the necessary data instead of selecting the entire data for a file. If a document has 5 fields, you need to display only 3, and then select only 3 fields.Find () methodMongoDB's Find () method, which is

MongoDB projection means to select only the necessary data instead of selecting the entire data for a file. If a document has 5 fields, you need to display only 3, and then select only 3 fields.Find () methodMongoDB's Find () method, which is

MongDB basic learning (5) -- projection, paging, sorting, aggregation, and mongdb Paging MongDB basic learning (5) -- projection, paging, sorting, and aggregation Basic syntax Learning The Chinese New Year is coming soon, tomorrow is a lover, and

MONGDB Basic Learning (v)--projection, pagination, sorting, aggregationThe learning of Basic grammarThe new Year is coming soon, tomorrow is a lover, the day after tomorrow will be a holiday, hope that they can in the holiday before the five and six

In the four CRUD operations, a record or document is obtained from the collection of mongodb databases. For non-DBAs, query is the most used. Therefore, if you have learned the query, it will be of great help for us to better operate the database in

The MongoDB query document uses the Find () method. The Find () method displays all documents in an unstructured manner. Grammar Db.collection.find (query, projection) query: Optional, use the query operator to specify the query

Brief introduction MongoDB is a NoSQL database based on distributed file storage Written by the C + + language, stable and high performance Designed to deliver scalable, high-performance data storage solutions for WEB applications

Mongodb advanced 2: mongodb aggregation and mongodb advanced AggregationIn the previous article we talked about mongodb's advanced query: http://blog.csdn.net/stronglyh/article/details/46817789 This article introduces mongodb aggregation. I. mongodb

Learning MongoDB 6: MongoDB query (cursor operation, cursor information) (3), mongodb cursorI. Introduction Db. collection. find () can be used to query based on conditions and specify fields returned using the projection operator to omit this