## Brin Index在 Greenplum 7中的理论与实现 --《Greenplum 7 新版本大剧透》系列直播 讲师：陈金豹，Greenplum内核研发 活动时间：2021年4月28日 20:00 - 21:00 #### 欢迎访问Greenplum中文社区：cn.greenplum.org ## Brin Index 在Greenplum 7中的理论与实践 陈金豹, VMWare内核工程师 ## 目录 Brin Index On Heap AppendOnly Table Brin在AppendOnly Table上的实现 性能测试 ## Block Range Index 存储数据块中元组字段的最大最小值，用于过滤不符合条件的数据块 1c443857/p6_2.jpg) ## Brin的优势和劣势 优势： 占用空间小 创建快 劣势： 只有在数据具有一定分布特点时才有用 ## Brin的体积 Brin tuple: 20bytes Block Range: 8K * 20 = 160K Brin比Heap小8000倍 1 TB的Heap表只需要125M的Brin Block Rang ![Image](/

Shapefile Dumper 52 4.9 Spatial Indexes 52 4.9.1 GiST Indexes 53 4.9.2 BRIN Indexes 53 4.9.3 SP-GiST Indexes 55 4.9.4 Tuning Index Usage 56 5 Spatial Queries 57 5.1 Determining Spatial Relationships PostgreSQL releases, X3D support, TIGER geocoder support, management functions. Darafei Praliaskouski Index improvements, bug fixing and geometry/geography function improvements, SFCGAL, raster, GitHub curation project. General bug fixing, geography support, geography and geometry index support (2D, 3D, nD index and anything spatial index), underlying geometry internal structures, GEOS functionality integration

7.6.2 TiFlash_schema_apply_duration ..... 278 7.6.3 TiFlash_raft_read_index_duration ..... 278 7.6.4 TiFlash_raft_wait_index_duration ..... 279 故障诊断 ..... 279 8.1 慢查询日志 ..... 279 8.1.1 日志示例 警告： 该版本存在一些已知问题，已在新版本中修复，建议使用 5.2.x 的最新版本。 在 5.2 版本中，你可以获得以下关键特性： · 支持基于部分函数创建表达式索引 (Expression index)，极大提升查询的性能。 · 提升优化器的估算准确度 (Cardinality Estimation)，有助于选中最优的执行计划。 · 锁视图 (Lock View) 成为 GA 特性，提供更 证书，默认值为false。表示statement summary tables中保存的SQL种类的最大数量。默认值从200修改为3000。废弃TiDB配置文件中allow-expression-index配置项对请求进行攒批的控制开关，开启后可显著提升写入性能。默认值为true。TiDB 配置文件security.auto-tls

0 码力 | 2259 页 | 48.16 MB | 2 年前

3

MaterializeMySQL Database Engine • Custom HTTP Handler • MySQL Database Engine • BloomFilter Skipping Index • Query Predicate Optimizer • And more ~ 400+ commit ); for (size_t index = 0; index < rows_data.size(); index += 2) { writeable_rows_mask[index + 1] = true; writeable_rows_mask[index] = differenceSortingKeys(DB::get(rows_data[index]), DB::get(rows_data[index + 1]), sorting_columns_index); } for (size_t index = 0; index < rows_data.size(); index += 2) { if (likely(

specific index ## ☀️ ☁️ ☁️ 1 In [149]: a.shape 2 Out $$ 149 $$ : torch.Size([4, 3, 28, 28]) 3 4 In [159]: a.index_select(0, 5 0ot{h50ens0o({h,S]iæ($hapa, 28, 28]) 6 7 In [167]: a.index_select(1 0at[h6?ns0o(h,S]z£($Hape, 28, 28]) 10 In [168]: a.index_select(2, torch.arange(28)).shape 11 Out[168]: torch.Size([4, 3, 28, 28]) 13 In [169]: a.index_select(2, torch.arange(8)).shape 14 Out[169]: torch 14 In [175]: torch.masked_select(x, mask).shape 15 Out[175]: torch.Size([3]) ## select by flatten index ## ● 5 In [177]: torch.take(src, torch.tensor([0, 2, 6 0])): tensor([4, 5, 8]) ## 下一课时 Tensor变换

.... 31 9. Index Root Page — Type 0x06 ..... 36 10. Index B-Tree Page — Type 0x07 — YOU ARE HERE ..... 41 10.1. B-Tree Header ..... 41 10.2. Index Jump Info ..... 42 10.3. Index Jump Nodes . .... 43 10.4. Index Nodes ..... 43 10.5. Index Data ..... 43 11. Blob Data Page — Type 0x08 — TODO ..... 45 12. Generator Page — Type 0x09 ..... 46 12.1. Creating Lots Of Sequences ..... 52 onwards. The remaining pages consist of Index Root Pages (page type 0x06), Transaction Inventory Pages or TIP (page type 0x03), Pointer Pages (page type 0x04), Index BTree Pages (page type 0x07), Data Pages

869 9.7.2 TiFlash_schema_apply_duration ··· 869 9.7.3 TiFlash_raft_read_index_duration ··· 870 9.7.4 TiFlash_raft_wait_index_duration ··· 870 9.8 自定义监控组件的配置 ··· 870 9.8.1 自定义 Prometheus 配置 ··· 871 Continuous Profiling ··· 4586 17.4 D ··· 4587 17.4.1 Dynamic Pruning ··· 4587 17.5 I ··· 4587 17.5.1 Index Merge ··· 4587 17.5.2 In-Memory Pessimistic Lock ··· 4587 17.6 L ··· 4587 17.6.1 Leader/Follower/Learner PDF查看两个LTS版本之间的所有release notes。下表列出了从7.2.0到7.5.0的一些关键特性： 分类 功能 描述 可扩展性与性能 支持并行运行多个 ADD INDEX 语句 通过该功能，为同一个表添加多个索引的任务可以变为并发运行。以前同时运行2个添加索引语句X和 $ \hookrightarrow $ Y需要花费X的时间+Y的时间，现在在一

Frequently Asked Questions 8. PostGIS Raster Frequently Asked Questions 9. PostGIS Special Functions Index PostGIS Aggregate Functions PostGIS Window Functions PostGIS SQL-MM Compliant Functions PostGIS PostgreSQL releases, X3D support, TIGER geocoder support, management functions. ## Darafei Praliaskouski Index improvements, bug fixing and geometry/geography function improvements, SFCGAL, raster, GitHub curation project. General bug fixing, geography support, geography and geometry index support (2D, 3D, nD index and anything spatial index), underlying geometry internal structures, GEOS functionality integration

Shapefile Dumper 50 4.9 Spatial Indexes 50 4.9.1 GiST Indexes 51 4.9.2 BRIN Indexes 51 4.9.3 SP-GiST Indexes 53 4.9.4 Tuning Index Usage 53 5 Spatial Queries 55 5.1 Determining Spatial Relationships 14.2.17 Topology_Load_Tiger 739 14.2.18 Set_Geocode_Setting 741 # 5 PostGIS Special Functions Index 743 15.1 PostGIS Aggregate Functions 743 15.2 PostGIS Window Functions 743 15.3 PostGIS SQL-MM PostgreSQL releases, X3D support, TIGER geocoder support, management functions. Darafei Praliaskouski Index improvements, bug fixing and geometry/geography function improvements, SFCGAL, raster, GitHub curation

Shapefile Dumper 52 4.9 Spatial Indexes 52 4.9.1 GiST Indexes 53 4.9.2 BRIN Indexes 53 4.9.3 SP-GiST Indexes 55 4.9.4 Tuning Index Usage 56 5 Spatial Queries 57 5.1 Determining Spatial Relationships PostgreSQL releases, X3D support, TIGER geocoder support, management functions. Darafei Praliaskouski Index improvements, bug fixing and geometry/geography function improvements, SFCGAL, raster, GitHub curation project. General bug fixing, geography support, geography and geometry index support (2D, 3D, nD index and anything spatial index), underlying geometry internal structures, GEOS functionality integration