Cache Database

Cache database Introduction:
NoSQL (Not Only SQL), which means "not only SQL" refers to non-relational database, with Internet web2.0 (user-generated content) the rise of websites, traditional relational databases in dealing with web2 .0 sites, especially large scale and high concurrent SNS (social network) of web2.0 pure dynamic site has appeared to be inadequate, exposed a lot of problems difficult to overcome, rather than a relational database due to its own characteristics has been very fast growing. NoSQL database is generated in order to solve large-scale data collection of multiple data types of challenges brought about, especially in big data application problems.
Four classification database NoSQL
first category: the key (Key-Value) stored in a database:
this type of databases will be used primarily to a hash table, this table has a specific key and a pointer to the specific data. Key / value model for IT systems has the advantage of simplicity, ease of deployment. But when the DBA if only part of the value to query or update, Key / value becomes inefficient up. Such as: Tokyo Cabinet / Tyrant, Redis, Voldemort, Oracle BDB.
The second category: storing a database column
which is typically part of a database used to deal with distributed mass data storage. Key still exists, but they are characterized by pointing to a number of columns. These columns are made to the family to arrange. Such as: Cassandra, HBase, Riak.
The third category: document database
inspiration document database from Lotus Notes office software, and it is similar with the first key-value store. This type of data model version of the document, in a semi-structured document stored in a particular format, such as JSON. Document database can be seen as an upgraded version of the key database, nested between the keys allowed. And document database query efficiency higher than the key database. Such as:. CouchDB, MongoDb There are also a document database SequoiaDB, it has been open source.
Class IV: Graphics (Graph) database
database ranks with other graphical structure and the rigid structure of the different SQL databases, it uses a flexible graphical models, and can be extended to multiple servers. NoSQL database is not a standard query language (SQL), database query and therefore the need to develop a data model. Many NoSQL databases are REST-style interface or data query API. [2] such as: Neo4J, InfoGrid, Infinite Graph.
Therefore, we conclude that NoSQL database more applicable in this case several of the following situations: 1 data model is relatively simple; 2 needs more flexibility in IT systems; three pairs. high performance database requirements; 4 does not require a high degree of data consistency; 5. for a given key, relatively easy to map complex environment value.