redis vs cassandra

Reference http://zhaoyanblog.com/archives/307.htmlModifying the Cassandra.yaml configuration filePut the defaultAuthenticator:allowallauthenticatorChange intoAuthenticator:passwordauthenticatorStart CassandraCQL connection, Cassandra is the default account and password./cqlsh-ucassandra-pcassandra IP PortCreate user' MyPassword ' SUPERUSER;There are two kinds of users here, one is Superuser, one is NosuperuserCqlsh after exiting, login with new userDr

Save data to Cassandra in Spark-shell:vardata = Normalfill.map (line = Line.split ("\u0005")) Data.map ( line= = (Line (0), Line (1), Line (2)) . Savetocassandra ("Cui", "Oper_ios", Somecolumns ("User_no","cust_id","Oper_code","Oper_time"))Savetocassandra method when the field type is counter, the default behavior is countCREATE TABLE CUI.INCR (Name text,Count counter,PRIMARY KEY (name))scala> var rdd = Sc.parallelize (Array (("Cui", 100))rdd:org.apa

First, set the user name and passwordModifying the Cassandra.yaml configuration filePut the defaultAuthenticator:allowallauthenticatorChange intoAuthenticator:passwordauthenticatorIf you need to log in and view the Modify permissions, you need to modifyAuthorizer:allowallauthorizerForAuthorizer:cassandraauthorizerStart CassandraCQL connection, Cassandra is the default account and password./cqlsh-u cassandra

1. If we are going to reboot Cassandra recommend that you save the data in DB before restarting Instructions: ./bin/nodetool--h 127.0.0.1 Flush 2. View the operation of each node in a clustered environment: ./bin/nodetool--h 127.0.0.1 Ring Address DCs Rack Status State Load owns Token133857208900194687050142871119212531697192.168.11.185 Datacenter1 Rack1 DownNormal? 91.45% 119317112008803869636148387431580597032192.168.11.124 datacenter1 rack1 up Nor

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 fairness, we did the following: 1. All the loop variables are placed outside the loop 2. For Cassandra, the Replication-factor setting is 1, so inserting the data d

Immediately above: http://blog.csdn.net/kunshan_shenbin/article/details/7100713 Resources: http://zhangliancheng.com/2011/04/cassandra-cluster-setup-in-ubuntu/ Http://wiki.apache.org/cassandra/MultinodeCluster_JP Let's assume nodea-ip:192.168.11.124 nodeb-ip:192.168.11.185 1. Modify Rpc_address: In the manner mentioned in (Single-node) above, modify the Nodea,nodeb configuration in turn: Cassandra.yaml fil

the principle of failure detection in Cassandra Blog Categories:Cassandra Cloud Cassandra Source failure detection phi failure detection Cassandra principle of failure detection in first, traditional failure detection and its deficiencies Traditional failure detection methods In a distributed system, the Heartbeat (Heartbeat) is often used to detect the health

After installing Cassandra, we begin to experience the query of this database, the traditional relational database uses SQL to query, and Cassandra uses the CQL.CQL Grammar is still a lot of, here do not elaborate, also not this necessary, specific documents countless, here just the most commonly used query function listed.Start by opening the command line (or PowerShell) to the Bin folder in the

(i) the role of gossipThe Cassandra Cluster has no central node and each node has the same status, and they maintain the state of the cluster through a protocol called gossip.By gossip, each node knows which nodes are in the cluster and the state of those nodes, which makes it possible for any node in the Cassandra Cluster to route any key, and any node that is unavailable will not have disastrous consequen

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 Model: In Cassandra, the application data is present in the keyspace, which corresponds to the schema in the relati

(i) the role of gossipThe Cassandra Cluster does not have a central node, and each node is in exactly the same position, and they maintain the state of the cluster through a protocol called gossip.With gossip, each node can know which nodes are included in the cluster, and the state of those nodes, which allows any node in the Cassandra Cluster to route any key, and any node that is unavailable will have no

in the system architecture of each name enterprise. Today, there are many types of nosql products, such as Membase, MongoDB, Apache Cassandra, COUCHDB, and so forth. However, at home and abroad internet giants such as social giants such as Sina Weibo, media giant Viacom and picture-sharing leader Pinterest , and other companies have adopted the Redis as its NoSQL database choice, Where exactly is

Run the CQL language in the window environment first install the Python environment, not required under Linux, Cassandra built-in Python.1. View python version: Python--version2. Run Pythod:python./cqlshA. CQL definition statement:Keyspace:3. See the Help for creating a keyspace: helping create keyspace;4. Create Keyspace:create keyspace ks1 with replication = {' class ': ' Simplestrategy ', ' Replication_factor ': 1};5. View the structure of the keys

Clear all the data in the tableTruncate Falcon_gps;TRUNCATEAccepts a argument for the column family name, and permanently removes all data from said column family.Query Cassandra a table an empty how many rows of recordsSelect COUNT (*) from Falcon_gps;Bulk Import dataBEGIN BATCH USING Consistency QUORUM and TTL 8640000 INSERT into users (KEY, password, name) VALUES (' User2 ', ' [email prot Ected] ', ' second user ') UPDATE users SET password = ' Ps2

Cassandra Run appears unable to gossip with any seeds,cqlsh link not on, prompting connection refused treatment methodProblem descriptionWhen Cassandra is started, it appears:Java.lang.RuntimeException:Unable to gossip with any seeds at Org.apache.cassandra.gms.Gossiper.doShadowRound ( gossiper.java:1160) at Org.apache.cassandra.service.StorageService.checkForEndpointCollision (Storageservice.java : 416) at

The newly written dirty data is in the memory memtable table. Therefore, you must have an organic mechanism to ensure that the data in the memory can be restored in case of exceptions. And relational database system 1Example: Cassandra also uses the method of first writing logs and then writing data. Its logs are called commitlog. Unlike memtable/sstable,Commitlog is server-level, not column family-level.The size of each commitlog file is fixed.Segmen

The login verification mechanism of Cassandra is independent and the data is shared by the clusterReference: http://blog.csdn.net/y_y_y_k_k_k_k/article/category/59433571, the initial installation after the login is like this:2, in the relational database, we generally have a user name, password login, then Cassandra How to configure, you must use the user name password login it.Very simple, modify the confi

Big Data Technology route choice for small and medium-sized enterprises (ii)-CASSANDRA+PRESTO programmeI have written before: small and medium-sized enterprise's big data technology route choice and low-key, luxurious, has the connotation agile Big Data solution: Flume+cassandra+presto+spagobi.It took the last two months to finally pass the Cassandra+presto+spago

The demo is as follows:CREATE TABLEUsers3 (user_id text PRIMARY KEY, first_nametext, Last_Nametext, emails listtext>);INSERT intoUSERS3 (user_id, first_name, last_name, emails)VALUES('Frodo','Frodo','Baggins',[' [email protected] ', ' [email protected] ']);UPDATEUsers3SETEmails=Emails+ [' [email protected] '] WHERE user_id = 'Frodo'; SELECT user_id, emails fromUsers3WHERE user_id = 'Frodo';Collection typeA Collection column is declared using the collection type, followed by another type, such i

Cassandra, as a NOSQL database, selects AP in the CAP principle, which can be used for sex and partition tolerance, and is guaranteed by final consistency in data consistency, using an extension of final consistency--tunable consistency. For any read-write operation, the client application determines the level of conformance for the requested data, Cassandra then responds to the request based on the request