Apache CouchDB is a NoSQL database system, free open source document oriented written in Erlang. Partial updates during the flush will be discarded.If the failure occurred while committing the header, a surviving copy of the previous identical headers will remain, ensuring coherency of all previously committed data. It makes some operations faster in NoSQL. Except the header area, consistency checks or fix-ups after a crash or a power failure are never necessary.Whenever the space in the database file got wasted above certain extent, all the active data will be copied (cloned) to a new file. So you have to create an admin account for CouchDB. End of … The long-awaited 3.0 release of the Apache CouchDB open source NoSQL database was announced this week. You can install it with the following command:Next, create an Apache CouchDB repo using the command below:Save and close the file after you finish. It provides the facility of storing documents with unique names, and it also provides an API called RESTful HTTP API for reading and updating (add, edit, delete) database documents.In CouchDB, documents are the primary unit of data and they also include metadata. Then, install Apache CouchDB using the following command:After the installation is successfully completed, you can proceed to the next step.You can configure CouchDB as standalone mode or in clustered mode. One feature that sets Couchbase apart, not just from other NoSQL competition but from its predecessor CouchDB, is its SQL-like query language called N1QL (pronounced “nickel”). For quite some time relational database, such as MYSQL ,Oracle and Microsoft SQL Server, have been used to store data for most Application .With the Web growing rapidly , spawning enormous ,user-generated content websites such as Facebook ,Twitter, These databases store both structured data and unstructured data like audio files, video files, documents, etc. And the simple structure of HTTP resources and methods (GET, PUT, DELETE) are easy to understand and use.As we store data in the flexible document-based structure, there is no need to worry about the structure of the data.Users are provided with powerful data mapping, which allows querying, combining, and filtering the information.CouchDB provides easy-to-use replication, using which you can copy, share, and synchronize the data between databases and machines.Database is the outermost data structure/container in CouchDB.Each database is a collection of independent documents.Each document maintains its own data and self-contained schema.Document metadata contains revision information, which makes it possible to merge the differences occurred while the databases were disconnected.CouchDB implements multi version concurrency control, to avoid the need to lock the database field during writes.CouchDB is a document storage NoSQL database. Key-value model—the least complex NoSQL option, which stores data in a schema-less way that consists of indexed keys and values.Examples: Cassandra, Azure, LevelDB, and Riak. The database will not have any partially saved or edited documents. For a database to store the information in a secured manner, it is required to provide confidentiality, integrity, and availability which is collectively known as CIA. NoSQL databases have been recently gaining traction with popular options such as MongoDB, CouchDB, Redis, and Apache Cassandra, even though they’ve existed since the 1960s. You can allow it with the following command:After completion, you can proceed to the next step.At this point, CouchDB is installed and configured. You will see the CouchDB dashboard in the following screen:CouchDB also allows you to create and delete databases using the curl command.To create a database named testdb on CouchDB, run the following command:To create a database named userdb on CouchDB, run the following command:You can also verify the database using the curl command as shown below:You can also refresh the CouchDB dashboard to view the database in your web browser.If you want to delete the testdb database, run the following command:Congratulations! A NoSQL (originally referring to "non-SQL" or "non-relational") database provides a mechanism for storage and retrieval of data that is modeled in means other than the tabular relations used in relational databases.Such databases have existed since the late 1960s, but the name "NoSQL" was only coined in the early 21st century, triggered by the needs of Web 2.0 companies. It has been a trend to employ NoSQL database in the modern application system development for either local or cloud platforms.
Then, start the CouchDB service and activate it to start at boot:You can now verify the status of the CouchDB service using the following command:You can also check the listening port of CouchDB with the following command:By default, SELinux is activated on your system. SQL vs NoSQL Security. You can create one by editing the local.ini file:Set the bind-address to 0.0.0.0 to allow access from an external IP address and also set the admin password in the [admin] section as shown below:Save and close the file after you finish.
Compared to other relational databases, it does not store data and relationships in tables. So it is recommended to disable SELinux on your system.You can disable SELinux by editing / etc / selinux / config file:Save and close the file.