 Apache Cassandra static column 介绍与实战username 只会有一个 email 和 encrypted_password 。 注意,不是任何表都支持给列加上 STATIC 关键字的,静态列有以下限制。 如果表没有定义 Clustering columns(又称 Clustering key),这种情况是不能添加静态列的。如下: cqlsh:iteblog_keyspace> CREATE TABLE "iteblog_users_with_s useful (and thus allowed) if the table has at least one clustering column" iteblog_users_with_status_updates_invalid 表只有 PRIMARY KEY,没有定义 clustering column,不支持创建 Static columns。这是因为静态列在同一个 partition key key 存在多行的情况下才能达到最优情况,而且行数越多效果也好。但是如果没有定义 clustering column,相同 PRIMARY KEY 的数据在同一个分区里面只存在一行数据,本质上就是静态的,所以没必要支持静态列。 如果建表的时候指定了 COMPACT STORAGE,这时候也不允许存在静态列: cqlsh:iteblog_keyspace> CREATE TABLE "iteblog_0 码力 | 5 页 | 0 Bytes | 1 年前3 Apache Cassandra static column 介绍与实战username 只会有一个 email 和 encrypted_password 。 注意,不是任何表都支持给列加上 STATIC 关键字的,静态列有以下限制。 如果表没有定义 Clustering columns(又称 Clustering key),这种情况是不能添加静态列的。如下: cqlsh:iteblog_keyspace> CREATE TABLE "iteblog_users_with_s useful (and thus allowed) if the table has at least one clustering column" iteblog_users_with_status_updates_invalid 表只有 PRIMARY KEY,没有定义 clustering column,不支持创建 Static columns。这是因为静态列在同一个 partition key key 存在多行的情况下才能达到最优情况,而且行数越多效果也好。但是如果没有定义 clustering column,相同 PRIMARY KEY 的数据在同一个分区里面只存在一行数据,本质上就是静态的,所以没必要支持静态列。 如果建表的时候指定了 COMPACT STORAGE,这时候也不允许存在静态列: cqlsh:iteblog_keyspace> CREATE TABLE "iteblog_0 码力 | 5 页 | 0 Bytes | 1 年前3
 Pivotal Greenplum 5.0 - 开源MPP 数据库的不二之选二年前 外部表 12月 11月 4月 3月 2月 5月 并行执行 企业级特性 Gemfire Chorus 使用场景 Text CLUSTERING REGRESSION CLASSIFICATION GRAPH GEOSPATIAL STRUCTURED QUERY LANGUAGE Greenplum 5.00 码力 | 18 页 | 913.39 KB | 1 年前3 Pivotal Greenplum 5.0 - 开源MPP 数据库的不二之选二年前 外部表 12月 11月 4月 3月 2月 5月 并行执行 企业级特性 Gemfire Chorus 使用场景 Text CLUSTERING REGRESSION CLASSIFICATION GRAPH GEOSPATIAL STRUCTURED QUERY LANGUAGE Greenplum 5.00 码力 | 18 页 | 913.39 KB | 1 年前3
 Using MySQL for Distributed Database ArchitecturesAvailability with MySQL Cold Standby (ie DRBD) Failover (Classical Replication) Active-Active Clustering (PXC, MySQL Group Replication) © 2018 Percona. 12 Q1:What Failure Modes Do you Consider ?0 码力 | 67 页 | 4.10 MB | 1 年前3 Using MySQL for Distributed Database ArchitecturesAvailability with MySQL Cold Standby (ie DRBD) Failover (Classical Replication) Active-Active Clustering (PXC, MySQL Group Replication) © 2018 Percona. 12 Q1:What Failure Modes Do you Consider ?0 码力 | 67 页 | 4.10 MB | 1 年前3
 TIDB The Large Scale Relational Database Solutionthat would most benefit from this Database solution are: TiDB focuses on scalability, database clustering, and its ability to automatically scale horizontally (across nodes/instances/ machines), another0 码力 | 12 页 | 5.61 MB | 6 月前3 TIDB The Large Scale Relational Database Solutionthat would most benefit from this Database solution are: TiDB focuses on scalability, database clustering, and its ability to automatically scale horizontally (across nodes/instances/ machines), another0 码力 | 12 页 | 5.61 MB | 6 月前3
 Cassandra在饿了么的应用,哪个节点应该存放数据的第一份拷贝。 基本上,Partitioner就是一个计算分区键token的哈希函数。 1.Partition Key 决定数据在Cassandra哪个节点上 2.Clustering Key 用于在各个分区内的排序 3.Primary Key 主键,决定数据行的唯一性 Partitioner 1.Key_part_one,key_part_two共同构成了primary0 码力 | 40 页 | 4.95 MB | 1 年前3 Cassandra在饿了么的应用,哪个节点应该存放数据的第一份拷贝。 基本上,Partitioner就是一个计算分区键token的哈希函数。 1.Partition Key 决定数据在Cassandra哪个节点上 2.Clustering Key 用于在各个分区内的排序 3.Primary Key 主键,决定数据行的唯一性 Partitioner 1.Key_part_one,key_part_two共同构成了primary0 码力 | 40 页 | 4.95 MB | 1 年前3
 Greenplum机器学习⼯具集和案例(CRF) Time Series Analysis • ARIMA Unsupervised Learning AssociaDon Rules (Apriori) Clustering (k-Means) Topic Modelling (Latent Dirichlet AllocaDon) Utility FuncJons Conjugate0 码力 | 58 页 | 1.97 MB | 1 年前3 Greenplum机器学习⼯具集和案例(CRF) Time Series Analysis • ARIMA Unsupervised Learning AssociaDon Rules (Apriori) Clustering (k-Means) Topic Modelling (Latent Dirichlet AllocaDon) Utility FuncJons Conjugate0 码力 | 58 页 | 1.97 MB | 1 年前3
 Pentest-Report Vitess 02.2019all SQL values covered by SQL redaction (Low) Conclusions Introduction “Vitess is a database clustering system for horizontal scaling of MySQL” From https://vitess.io/ This report documents the results0 码力 | 9 页 | 155.02 KB | 1 年前3 Pentest-Report Vitess 02.2019all SQL values covered by SQL redaction (Low) Conclusions Introduction “Vitess is a database clustering system for horizontal scaling of MySQL” From https://vitess.io/ This report documents the results0 码力 | 9 页 | 155.02 KB | 1 年前3
 PostgreSQL 8.2 Documentationforeign key constraint triggers. index_name The index name on which the table should be marked for clustering. storage_parameter The name of a table storage parameter. value The new value for a table storage tablename. When a table is clustered, it is physically reordered based on the index information. Clustering is a one- time operation: when the table is subsequently updated, the changes are not clustered at least equal to the sum of the table size and the index sizes. Because CLUSTER remembers the clustering information, one can cluster the tables one wants clustered manually the first time, and setup0 码力 | 1748 页 | 13.12 MB | 1 年前3 PostgreSQL 8.2 Documentationforeign key constraint triggers. index_name The index name on which the table should be marked for clustering. storage_parameter The name of a table storage parameter. value The new value for a table storage tablename. When a table is clustered, it is physically reordered based on the index information. Clustering is a one- time operation: when the table is subsequently updated, the changes are not clustered at least equal to the sum of the table size and the index sizes. Because CLUSTER remembers the clustering information, one can cluster the tables one wants clustered manually the first time, and setup0 码力 | 1748 页 | 13.12 MB | 1 年前3
 VMware Greenplum v6.18 DocumentationDatabase 6.7 includes MADlib version 1.17, which introduces new Deep Learning features, k-Means clustering, and other improvements and bug fixes. See the Apache MADlib page for additional information and Database 6.6 includes MADlib version 1.17, which introduces new Deep Learning features, k-Means clustering, and other improvements and bug fixes. See the MADlib 1.17 Release Notes for a complete list of science problems are solved using a combination of models, with graphs being just one. Regression, clustering, and other methods available in Greenplum, make for a powerful combination. 4. Greenplum offers0 码力 | 1959 页 | 19.73 MB | 1 年前3 VMware Greenplum v6.18 DocumentationDatabase 6.7 includes MADlib version 1.17, which introduces new Deep Learning features, k-Means clustering, and other improvements and bug fixes. See the Apache MADlib page for additional information and Database 6.6 includes MADlib version 1.17, which introduces new Deep Learning features, k-Means clustering, and other improvements and bug fixes. See the MADlib 1.17 Release Notes for a complete list of science problems are solved using a combination of models, with graphs being just one. Regression, clustering, and other methods available in Greenplum, make for a powerful combination. 4. Greenplum offers0 码力 | 1959 页 | 19.73 MB | 1 年前3
 VMware Greenplum v6.19 DocumentationDatabase 6.7 includes MADlib version 1.17, which introduces new Deep Learning features, k-Means clustering, and other improvements and bug fixes. See the Apache MADlib page for additional information and Database 6.6 includes MADlib version 1.17, which introduces new Deep Learning features, k-Means clustering, and other improvements and bug fixes. See the MADlib 1.17 Release Notes for a complete list of science problems are solved using a combination of models, with graphs being just one. Regression, clustering, and other methods available in Greenplum, make for a powerful combination. 4. Greenplum offers0 码力 | 1972 页 | 20.05 MB | 1 年前3 VMware Greenplum v6.19 DocumentationDatabase 6.7 includes MADlib version 1.17, which introduces new Deep Learning features, k-Means clustering, and other improvements and bug fixes. See the Apache MADlib page for additional information and Database 6.6 includes MADlib version 1.17, which introduces new Deep Learning features, k-Means clustering, and other improvements and bug fixes. See the MADlib 1.17 Release Notes for a complete list of science problems are solved using a combination of models, with graphs being just one. Regression, clustering, and other methods available in Greenplum, make for a powerful combination. 4. Greenplum offers0 码力 | 1972 页 | 20.05 MB | 1 年前3
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