Mongodb Query List

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 ...

In our daily life, we are inseparable from the application of position recognition class. Apps like Foursquare and Facebook help us share our current location (or the sights we're visiting) with our family and friends. Apps like Google Local help us find out what services or businesses we need around our current location. So, if we need to find a café that's closest to us, we can get a quick suggestion via Google Local and start right away. This not only greatly facilitates the daily life, ...

Serendip is a social music service, used as a http://www.aliyun.com/zixun/aggregation/10585.html "> Music sharing" between friends. Based on the "people to clustering" this reason, users have a great chance to find their favorite music friends. Serendip is built on AWS, using a stack that includes Scala (and some Java), Akka (for concurrency), play framework (for Web and API front-end ...).

Serendip is a social music service, used as a http://www.aliyun.com/zixun/aggregation/10585.html "> Music sharing" between friends. Based on the "people to clustering" this reason, users have a great chance to find their favorite music friends. Serendip is built on AWS, using a stack that includes Scala (and some Java), Akka (for concurrency), play framework (for Web and API front-end ...).

1: A simple introduction MongoDB is a distributed document database, supporting the master-slave structure of similar closed-type database, the document is stored in binary http://www.aliyun.com/zixun/aggregation/16702.html ">json form", No locks, no transactions, indexed. 2: Installation Steps Step one: Download the assembly http://www.mongodb.org/downloads Part II: Extract and extract the relevant bin directory to C ...

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 ({...).

At the beginning of September, rhttp://www.aliyun.com/zixun/aggregation/13461.html ">mongodb officially released the revised version, which means The language of the numerical calculation can also be in line with the NoSQL product, but in view of my side does not have the company really to use the Union of R and MongoDB, so in the efficiency question, we also dare not take lightly, therefore did one such test. The test environment is 8 cores, 64-bit machines. be used for ...

Recently, Thumbtack published two papers, namely ultra-high performance NoSQL benchmark and nosql failover characteristics, the former is the analysis of durability and performance trade-offs, the latter is about Aerospike, Cassandra, Couchbase and MongoDB several NoSQL fault-transfer features. All two benchmarks try to test "user-oriented applications with high throughput and low latency requirements, which can be stored using key-value forms." To make a thumback.

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 ...