mongodb dbref query

MongoDB dbref (Associative insert, query, delete) instance in depth, A,b,c three collection are interrelated. The number is the value of document.The introduction to Dbref can be seen http://blog.csdn.net/crazyjixiang/article/details/6616678 this

, A, B, and C collections are correlated. The number is the value of document. For more information about dbref, see the http://blog.csdn.net/crazyjixiang/article/details/6616678 article. Create a collection first. > var a={value:"1"}> var b={value:

"Database Commands""How the Command Works"The commands in MongoDB are actually implemented as a special type of query that is executed against the $cmd collection. RunCommand simply accepts the command document and executes the equivalent query, so>

@DBref The document association, when queried by that type, add the field name of the associated table to the field name, as follows:Criteria.where ("BlogGroup. $id"),$id represents the OID field of the associated table.OR and and union queriessuch

"Suzhou needs to work to add me QQ, the introduction of fee-splitting" MongoDB advanced1. Database commandsA. How the command worksDrop command to delete a collection in the shell and Execute Db.refactor.drop (). Actually, this function actually

This is a creation in Article, where the information may have evolved or changed. 2014-1-25 When you design a MONGO database, you encounter a problem where the log information table needs to reference the data from the people information table. If

Http://www.cnblogs.com/yoolonet/archive/2011/08/27/2155701.html A series of articles about MongoDB recently used MongoDB as a data storage system to record their own applications and problems in actual development. I hope this will be helpful to my

March 25 MongoDB (taken from "Humongous") 1.4 release shortly after its founder Dwight Merriman (formerly DoubleClick Ceo/cto) announced 10gen--open source document database MongoDB behind the company, It will provide business training and

Original address: http://keben1983.blog.163.com/blog/static/143638081201010591157929/ This document is translated from the [mongodb-docs-2010-10-24.pdf] [Java Language Center] section of the document and is organized according to your own

Because MongoDB is non-relational (join), references between documents ("Foreign keys") are usually solved by the client through additional queries to the server (linking ). These connections are always resolved on the client. It is very easy to do