cassandra

Recently SEOmoz released a new topic about Google algorithm changes. From 2000 to 2011, each upgrade has been detailed enumerated, as follows: 　　 Google's algorithm changes 500-600 times a year, but many changes are small. But every few

All nodes in the Cassandra cluster are peers, so read/write operations can occur on any node in the cluster, and perhaps this node does not require read/write data, so the node that interacts with the user becomes the coordinator node. Write

A relational database management system (RDBMS) is the most commonly used system for storing and using data, but the scalability of these databases is not very good for large amounts of data. In recent years, the concept of NoSQL has been widely

We are using DataStax Community Edition, the official website for the Cluster Control Center (opscenter) configuration is too brief, I tried 10 times to get it done: there should be no more detailed configuration instructions on the Internet. Here

Column in Cassandra is a ternary group {Name,value,timestamp} Name Name is required and has two ways of generating it: For the static column family, its value is specified by the administrator who created the column family. For dynamic column

To analyze the performance of inserting massive data into the Cassandra Cluster or Oracle, that is, the insertion rate, we sampled the inserted data using a Java program, and finally plotted the sample results with Jfreechart. For the sake of

The snitch in Cassandra is used to tell the Cassandra network topology, such as the relative distance between the nodes, how the nodes are grouped, and the rack where the nodes are located, so that the user requests can be efficiently routed. Note:

Originally we in (192.168.129.34,192.168.129.35,192.168.129.39 three machine cluster in the correct set up, but in the Opscenter has not received accurate system statistics: I later studied it because the statistics were sent to this opscenter by

Nutch2.1 extends the storage layer through Gora, optionally using any of HBase, Accumulo, Cassandra, MySQL, Datafileavrostore, Avrostore to store data, but some of them are immature. In my repeated tests found that, overall, Nutch2.1 than Nutch1.6

The column family in the Cassandra corresponds to a table in the relational database that is used to store rows and fields. Column number in column family is not fixed In a relational database, each row contains the same number of fields. However,

This article is the first of the Cassandra Data Model design (all two), which contains some of the practices ebay uses to design the Cassandra data model. Some of the best practices we learned through our communities, some of which are new to us,

What is replication? In Cassandra, replication is the storage of data to multiple nodes to ensure reliability and error tolerance. When you create a keyspace (equivalent to a table in a relational database), you must give a copy placement policy

Token is a very important concept in the Cassandra cluster because it affects the range of data that each node governs: We use the program to generate the token and then allocate it to each node: We use the following code to generate the token: #!

Cassandra Data storage structure The data in the Cassandra is divided into three main types: Commitlog: The main record of the data submitted by the client and operations. This data will be persisted to disk so that the data is not persisted to

Keyspace is a container for application data, which corresponds to a schema in a relational database. It is used to group column family. Each application in a cluster has only one keyspace. When you create a keyspace, you can specify a

Cassandra is a very popular NoSQL product, it is based on the Key-value distributed storage Way is respected by many DBAs. NoSQL database products range, compared with traditional relational database, in terms of technical maturity is not perfect,

When starting the Cassandra cluster, you need to choose how the data is divided in the cluster, which is done by Partitioner. All data managed in cluster is represented by the cyclization (ring). The loop is divided into a range (range) that equals

We now have a three-node Cassandra cluster on 192.168.129.34, 192.168.129.35, 192.168.129.39, because we have 7199 ports on each node (JMX monitor Port), So we can use Jconsole to detect the state of these nodes. Open the Jconsole

Detailed configuration of Cassandra Understanding the meaning of a software configuration item is a prerequisite for using this software, which details the meaning of each configuration item in the Cassandra configuration file (Storage-config.xml),

The Cassandra data model differs greatly from the model of a relational database: relational Database model: Data is stored in tables, data is followed by a paradigm to reduce redundancy, and tables are connected through foreign keys Cassandra