Cassandra Cassandra Cassandra Cassandra is an open-source distributed NoSQL database developed in Java. The distributed structure of Amazon's Dynamo, The data structure was developed by Facebook based on Google's BigTable databases. In 2009 it was transferred to Apache.
Cassandra Cassandra In addition, Cassandra tells us that we are not satisfied when we work with big data on relational databases; It also offers the advantages of high availability and linear scalability.
Cassandra Cassandra •Although it is not an Oracle or SQL Server, it is used by many world brands such as Youtube and Netflix in various products. •Easily scalable (Scalable) •Open Source •Fault tolerance management is available. •It is a NoSQL type that runs Wide Column Store / Column Families. •It can hold terabytes of data. •Data are automatically copied / replicated on many nodes.
General Features of CassandraGeneral Features of Cassandra After installing and running Cassandra (we do it with cassandra.bat) • Data entry can be done immediately from the command line. • To do this, run the cassandra_cli.bat file in the bin directory. • This is a command-line client and will connect to the Cassandra server. • An example is shown in the screenshot.
General Features of CassandraGeneral Features of Cassandra As you can see from the commands here, the database is actually a keyspace. The KEYSPACE statement corresponds to the “Database statement in relational databases. Creating a table in this keyspace actually means creating a Column Family. Row Keys set into Column Family can actually be compared to table rows that we know. Row Key contains columns and data in the form of key- value. Row Key: We can think of each table as a primary key. Each key-value column is actually associated with a Row Key.
General Features of CassandraGeneral Features of Cassandra As will be noted, there is key-value retention in the columns. The environment is purely case sensitive and for expressions to work; must be completed with.
General Features of CassandraGeneral Features of Cassandra With create keyspace, a keyspace called BigFootMotorCompany has been produced. A row key named Car was created by creating a column family. Column and key-value in Car are added with the set. With get, a column named ModelX was extracted.
First CommandsFirst Commands After this production, the folder structure will be formed as shown in the figure. Data is stored in binary format.
Cassandra TerminologyCassandra Terminology Node: The server on which any Cassandra instance is running. Cassandra data is stored here. Cluster: A cluster that contains one or more datacenter. CommitLog: Cassandra first writes data to commit a log to ensure durability. It provides a secure recovery mechanism against any failures on the server.
Cassandra TerminologyCassandra Terminology Memtables: Cassandra writes the data to the Memtables after the data is written to the commit log. Memtables are available on memory. SSTables (Sorted String Table): A literal data file. When a certain threshold is reached, the data on the Memtable is transferred here. SSTables are on the disk. Datacenter: A collection of one or more nodes. It can be separated logically or physically.
What is NoSQL?What is NoSQL? NoSQL is the conceptual name given to database systems in which you can store non-relational ”data in any schema format.
What is NoSQL?What is NoSQL? Imagine that we produce data somehow every day. For example, each movement of the companies in the picture creates a data set. These data are sometimes in a standard structure, usually in an unstructured structure. Incoming areas may change (increase, decrease) continuously. While 100 fields come in one data, the next number can increase to 200 fields. If we construct such a structure using Relational Database, it may be necessary to continuously update the table, column, index, trigger. Here noSQL works here. It saves us a great deal of trouble.
Briefly the benefits of NoSQLBriefly the benefits of NoSQL •Ability to store large data •Prevent data loss by storing data on multiple machines. •Ease of Use