Mongodb Query Reference

MongoDB company formerly known as 10gen, founded in 2007, in 2013 received a sum of 231 million U.S. dollars in financing, the company's market value has been increased to 1 billion U.S. dollar level, this height is well-known open source company Red Hat (founded in 1993) 20 's struggle results. High-performance, easy to expand has been the foothold of the MongoDB, while the specification of documents and interfaces to make it more popular with users, this point from the analysis of the results of Db-engines's score is not difficult to see-just 1 years, MongoDB finished the 7th ...

"51CTO classic" I like MongoDB mainly because it is so simple and natural to use it in dynamic languages. So far, I've used it in two projects (Encode and SPARRW), although I'm very happy with the choice, but there are some problems I haven't noticed, and these problems have kept me scratching my scalp for hours. If you have more than one machine, and then allocate a few more machines for the database, then some problems can be solved, but my project is running on a single (virtual) server on the low flow w ...

"Editor's note" in the "Pioneer" series of business, High-performance, Wang Tao to build beyond the MongoDB NoSQL, we and Wang Tao talk about High-performance, have a business sequoiadb build experience. Readers need to interpret the advantages of each nosql from the data, we also invited relevant experts at home and abroad to MongoDB, SEQUOIADB, Cassandra, hbase four NoSQL Benchmarking, and published test cases, related data and test rules. This time we will give you the test of domestic experts, ...

NoSQL Recent momentum is good, http://www.aliyun.com/zixun/aggregation/13461.html ">mongodb is one of the Jiao jiao, oneself learn nosql when also reference a lot of information, The final decision to start from the MongoDB, the most important reason has two: 1 oneself is a simple amateur, all problems I think whether there is a simple way to solve, rather stop to think a lot of time, also do not want to use stupid method to do immediately, and Mong ...

1.count Count returns the number of documents in the collection &http://www.aliyun.com/zixun/aggregation/37954.html ">nbsp;db.refactor.count () No matter how large the collection is, the number of documents can be returned quickly. You can pass the query, MongoDB calculates the number of query results Db.refactor.count ({...).

One-to-one relationship: Embed, such as http://www.aliyun.com/zixun/aggregation/10619.html "> User information collection has Address field, Address field has three fields of province, city, county. Modeling is as follows: a one-to-many relationship: An article has multiple comments, for 1 to multiple relationships because MongoDB has a size limit of 16M (higher than v1.8 ...) for single documents (document).

With the rise of internet web2.0 websites, the relational database has become a very hot new field, the development of the non relational database products is very rapid. 　　But the traditional relational database in dealing with web2.0 website, especially the super large-scale and high concurrent SNS type web2.0 pure dynamic website already appeared to be powerless, has exposed many insurmountable problems, for example: 1, high configured--to the database higher concurrent reads and writes the demand WEB2.0 website to be based on user personalized information to generate real-time dynamic ...

After completing one of the biggest projects of the year, the focus is shifting from PM's role to storage-related work, so it took some time outside of the work to focus on NoSQL related information (mainly from blog.nosqlfan.com) NoSQL related [translate] nosql ecosystem Http://blog.nosqlfan.com/html/2171.html//This is the best and most complete document I have seen NoSQL speak about nos ...

Big data has grown rapidly in all walks of life, and many organizations have been forced to look for new and creative ways to manage and control such a large amount of data, not only to manage and control data, but to analyze and tap the value to facilitate business development. Looking at big data, there have been a lot of disruptive technologies in the past few years, such as Hadoop, Mongdb, Spark, Impala, etc., and understanding these cutting-edge technologies will also help you better grasp the trend of large data development. It is true that in order to understand something, one must first understand the person concerned with the thing. So, ...

Big data has grown rapidly in all walks of life, and many organizations have been forced to look for new and creative ways to manage and control such a large amount of data, not only to manage and control data, but to analyze and tap the value to facilitate business development. Looking at big data, there have been a lot of disruptive technologies in the past few years, such as Hadoop, Mongdb, Spark, Impala, etc., and understanding these cutting-edge technologies will also help you better grasp the trend of large data development. It is true that in order to understand something, one must first understand the person concerned with the thing. So, ...