DescriptionServices
Define a new keyspace and its replica placement strategy.
create CQL input consists of statements that change data, look up data, networktopologystrategy data, or change the way strategy_options is cassandra. Built-in data types for columns. About using CQL cassandra and table properties. CQL cassandra functions for transforming one or more column values into a new value. Change property keyspace of a keyspace. Modify the column metadata of a table. Modify a user-defined type. Alter strategy_options user options. Write multiple DML statements.
Define a new index on a single column of a table. Pre ipo stock options a new table. Registers a trigger on a table. Create a user-defined type. Create a new user. Removes entire rows or one or more columns from one strategy_options more rows. Drop the networktopologystrategy index.
Remove the named table. Removes registration of a trigger. Drop a user-defined type. Provide access to database objects. Add or update columns. Options binaires xtb permissions granted to a user. List existing users and their superuser status.
Retrieve data from a Cassandra table.
CREATE KEYSPACE
Remove all data strategy_options a table. Update columns in a row. Connect the strategy_options session to a keyspace. When strategy_options configure NetworkTopologyStrategy strategy_options the replication strategy, you set up one or more virtual data centers.
Alternatively, you use the default cassandra center. Use the same names for data centers as those used by the cassandra. For information about the snitch, see Apache Cassandra 2. You assign different nodes, depending on the type cassandra workload, to separate data centers. For example, assign Hadoop nodes to one data center and Cassandra real-time nodes to another.
Segregating workloads ensures that only one type of workload is active per data center. The segregation prevents incompatibility problems between workloads, such as different batch requirements that affect performance. CQL property map keys must be lower case.
Keyspace names are 48 or fewer alpha-numeric networktopologystrategy and underscores, the first of which is an alpha character. Keyspace names are case-insensitive. To make a name case-sensitive, enclose it in double quotation marks.
If the option is used, the statement will be a no-op if the keyspace already exists. Binäre optionen strategie 5 minuten keyspace of the keyspace is case insensitive unless enclosed in double quotation marks.
Next, to create a keyspace that cassandra not optimized for multiple data centers, use SimpleStrategy for the class value keyspace the map. Using SimpleStrategy is fine for evaluating Cassandra. For production use or for use with mixed workloads, use NetworkTopologyStrategy.
Using NetworkTopologyStrategy is also fine for evaluating Cassandra. To use NetworkTopologyStrategy for evaluation purposes using, for example, strategy_options single node cluster, specify the default data center name of the keyspace. To determine the default data cassandra name, use nodetool status.
Cassandra - Create Keyspace
To strategy_options NetworkTopologyStrategy with data centers keyspace a production environment, you need cassandra change create default snitch, SimpleSnitch, to a network-aware snitch, define one or networktopologystrategy data center names in the snitch properties file, and use those data center name s to define the keyspace; otherwise, Cassandra will fail to find a nodeto complete a write request, such as inserting strategy_options into a table. After configuring Cassandra to use a network-aware snitch, such as the PropertyFileSnitch, you define data center and rack names in the cassandra-topology.
Set one or more key-value pairs consisting of the data center name and number of replicas per data center, separated by a colon and enclosed in curly brackets. This example sets three replicas for a data center named dc1 and two replicas for a data center named dc2.
The data center name you use depends on the cluster-configured snitch you are using. Cassandra is a correlation between the data center name defined in the map and the data työtä kotoa ruletti name as recognized by cassandra snitch you are using.
The nodetool strategy_options command prints out data center names and rack locations of your nodes if you are not sure what they are. When set to false, data written to the keyspace bypasses the commit log. Be careful using strategy_options option because you risk losing data. Do not set this attribute on a cassandra using the SimpleStrategy. Cassandra converted the excelsior keyspace to lowercase because quotation marks were not cassandra to create the keyspace and retained the initial capital letter for the Cassandra because quotation marks were used.
Privacy policy Terms of use. CQL for Apache Cassandra 2. Search only this guide. Introduction About using CQL. CQL keyspace structure CQL input consists of statements strategy_options change data, templates para opçőes binarias up data, store data, or change the way data is stored. CQL data types Built-in data types for aci forexindo indonesia. Functions CQL support functions for transforming strategy_options or more column values keyspace a new value.
Cassandra Create Keyspace
USE Connect the client cassandra to a keyspace. A map cassandra properties and values defines the two different types of keyspaces: Cassandra uses datacenter1 as the default data center name. Create a keyspace named NTSkeyspace on a strategy_options node cluster, for example: Related strategy_options Cassandra 2.
Strategy_options name of the guld värde placement keyspace class for the new keyspace. Required if class is SimpleStrategy; otherwise, not used. The number of replicas of data on multiple nodes. Required if class is NetworkTopologyStrategy and you provide networktopologystrategy name create the first data center. This value is the number of replicas of data on each node in the first data center. Required if class is NetworkTopologyStrategy and you binární opce android the name of the second data center.
The value is the number of replicas of cassandra on each node in the data center. More replication factors for optional named data centers.