Apache Cassandra static column 介绍与实战 Spark大数据博客 - https://www.iteblog.com Apache Cassandra static column 介绍与实战 假设我们有这样的场景：我们想在 Cassandra 中使用一张表记录用户基本信息（比如 email、密 码等）以及用户状态更新。我们知道，用户的基本信息一般很少会变动，但是状态会经常变化， 间。为了解决这种问题 ，Cassandra 引入了 static column。同一个 partition key 中被声明为 static 的列只有一个值的，也就是只存储一份。 如果想及时了 解Spark、Hadoop或者Hbase相关的文章，欢迎关注微信公共帐号：iteblog_hadoop 定义 static column 在表中将某个列定义为 STATIC 很简单，只需要在列的最后面加上 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

......................................................................................32 4.2.1. Column References...................................................................................... ...............52 5.5.1. Adding a Column................................................................................................52 5.5.2. Removing a Column ................................... .....................53 5.5.5. Changing a Column’s Default Value...................................................................54 5.5.6. Changing a Column’s Data Type .............................

Summary 324 Best Practices Summary 0 Data Model 324 Heap vs. Append-Optimized Storage 324 Row vs. Column Oriented Storage 324 Compression 325 Distributions 325 Resource Queue Memory Management 325 Partitioning Use the Least Space 337 Storage Model 337 Heap Storage or Append-Optimized Storage 338 Row or Column Orientation 338 Compression 339 Distributions 339 Local (Co-located) Joins 340 Data Skew 340 Processing Skew 341 Partitioning 341 Number of Partition and Columnar Storage Files 342 Indexes 343 Column Sequence and Byte Alignment 344 Memory and Resource Management with Resource Groups 344 Memory

Summary 315 Best Practices Summary 0 Data Model 315 Heap vs. Append-Optimized Storage 315 Row vs. Column Oriented Storage 315 Compression 316 Distributions 316 Resource Queue Memory Management 316 Partitioning Use the Least Space 328 Storage Model 328 Heap Storage or Append-Optimized Storage 329 Row or Column Orientation 329 Compression 330 Distributions 330 Local (Co-located) Joins 331 Data Skew 331 Processing Skew 332 Partitioning 332 Number of Partition and Columnar Storage Files 333 Indexes 334 Column Sequence and Byte Alignment 335 Memory and Resource Management with Resource Groups 335 Memory

Definition Basics 323 Default Column Values 324 Generated Columns 325 Creating and Managing Tables 326 Creating a Table 326 Choosing Column Data Types 326 Setting Table and Column Constraints 327 Check 333 Append-Optimized Storage 334 To create a heap table 334 Choosing Row or Column-Oriented Storage 334 To create a column-oriented table 335 Using Compression (Append-Optimized Tables Only) 336 To for Run-length Encoding 338 Adding Column-level Compression 338 Default Compression Values 340 Precedence of Compression Settings 340 Optimal Location for Column Compression Settings 341 Storage Parameters

Schemas 559 Creating and Managing Tables 559 Creating a Table 560 Choosing Column Data Types 560 Setting Table and Column Constraints 560 Check Constraints 561 Not-Null Constraints 561 Unique Constraints 566 Append-Optimized Storage 567 To create a heap table 567 Choosing Row or Column-Oriented Storage 567 To create a column-oriented table 568 Using Compression (Append-Optimized Tables Only) 569 To Documentation VMware by Broadcom 27 Adding Column-level Compression 572 Default Compression Values 573 Precedence of Compression Settings 573 Optimal Location for Column Compression Settings 574 Storage Directives

Schemas 530 Creating and Managing Tables 530 Creating a Table 531 Choosing Column Data Types 531 Setting Table and Column Constraints 531 Check Constraints 532 Not-Null Constraints 532 Unique Constraints 537 Append-Optimized Storage 538 To create a heap table 538 Choosing Row or Column-Oriented Storage 538 To create a column-oriented table 539 Using Compression (Append-Optimized Tables Only) 540 To for Run-length Encoding 542 Adding Column-level Compression 543 Default Compression Values 544 Precedence of Compression Settings 544 Optimal Location for Column Compression Settings 545 Storage Directives

Schemas 554 Creating and Managing Tables 554 Creating a Table 554 Choosing Column Data Types 555 Setting Table and Column Constraints 555 Check Constraints 556 Not-Null Constraints 556 Unique Constraints 561 Append-Optimized Storage 561 To create a heap table 562 Choosing Row or Column-Oriented Storage 562 To create a column-oriented table 563 VMware Greenplum 6 Documentation VMware, Inc 23 Using Compression for Run-length Encoding 566 Adding Column-level Compression 566 Default Compression Values 568 Precedence of Compression Settings 568 Optimal Location for Column Compression Settings 568 Storage Directives

Schemas 534 Creating and Managing Tables 534 Creating a Table 534 Choosing Column Data Types 534 Setting Table and Column Constraints 535 Check Constraints 535 Not-Null Constraints 536 Unique Constraints 541 Append-Optimized Storage 541 To create a heap table 541 Choosing Row or Column-Oriented Storage 541 To create a column-oriented table 542 Using Compression (Append-Optimized Tables Only) 543 To for Run-length Encoding 545 Adding Column-level Compression 545 Default Compression Values 547 Precedence of Compression Settings 547 Optimal Location for Column Compression Settings 547 Storage Directives

Schemas 531 Creating and Managing Tables 531 Creating a Table 531 Choosing Column Data Types 532 Setting Table and Column Constraints 532 Check Constraints 532 Not-Null Constraints 533 Unique Constraints 538 Append-Optimized Storage 538 To create a heap table 538 Choosing Row or Column-Oriented Storage 539 To create a column-oriented table 540 Using Compression (Append-Optimized Tables Only) 540 To Adding Column-level Compression 542 VMware Tanzu Greenplum 6 Documentation VMware, Inc. 23 Default Compression Values 544 Precedence of Compression Settings 544 Optimal Location for Column Compression