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1 Abstract 2 INTRODUCTION 本文为摘录，原文为： ../pdf/d/p1311-even.pdf 1 Abstract 2 INTRODUCTION What is a filter 属于近似查询 (approximate membership query), 用于判断独具是否在集合中。 如果输入在集合中，则必定输出 Yes 如果不在集合中，则输...

1 INTRODUCTION 本文为摘录，原文为： attachments/pdf/0/p1658-zhao.pdf QueryFormer: learning-based query planer representation model with tree-structured Transformer architecture -integrate histograms from database into query plan encoding 1 INTRODUCTION Physical Query Plan As DAG (Directed Acyclic Graph) Figure 1: Example query and query plan node 表示操作 edge 表示方向 子节点先执行，执行结果给...

1 ABSTRACT 本文为摘录，原文为： attachments/pdf/6/p1024-deep.pdf 1 ABSTRACT

1 TOOLS 1.1 top 1.2 ps 1.3 vmstat – Virtual Memory Statistics 1.4 sar – System Activity Repoter 1.5 perf 1.6 tubostat 1.7 iostat 1.8 irqbalance 1.9 ss – socket statistics 1.10 numastat 1.11 numad 本文为摘录，原文为： attachments/pdf/c/red_hat_enterprise_linux-7-performance_tuning_guide-en-us.pdf 1 TOOLS 1.1 top 1.2 ps 1.3 vmstat – Virtual Memory Statistics 1.4 sar – System Activity Repoter 1.5 perf 1.6 tubostat 1.7 iostat...

1 ABSTRACT 2 INTRODUCTION 本文为摘录，原文为： attachments/pdf/5/p2161-zhang.pdf 1 ABSTRACT 云存储中很大一部分数据很少被访问，被称为 冷数据 。 精确地识别和有效地管理成本效益高的存储中的冷数据是云提供商...

1 RTFM… 1.1 ipcs 1.2 ipcrm 2 Check shared memory in Linux 本文为摘录，原文为： https://linuxopsys.com/topics/check-shared-memory-in-linux 1 RTFM… 1.1 ipcs 1.2 ipcrm 2 Check shared memory in Linux Print active shared memory segments using -m option. # ipcs -m ------ Shared Memory Segments -------- key shmid owner perms bytes nattch status 0x00000000 65536 root 600...

1 ABSTRACT 2 INTRODUCTION 2.1 Range Filters 3 SNARF: A LEARNED FILTER 3.1 SNARF Description 本文为摘录，原文为： attachments/pdf/a/p1632-vaidya.pdf 1 ABSTRACT SNARF: Sparse Numerical Array-Based Range Filters 基于稀疏数组的范围过滤器 用于数值类型的范围过滤 2 INTRODUCTION Filters are space efficient but appropriate Answer membership queries on a...

1 INTRODUCTION 2 ARCHITECTURE 2.1 Modules 本文为摘录，原文为： attachments/pdf/2/p3535-gaffney.pdf 1 INTRODUCTION SQLite is embedded in the process of the host application Instead of communicating with a database server across process boundaries, applications manage a SQLite database by calling SQLite library functions several characteristics combine to make SQLite useful in a broad range of scenario: Cross-platform 数据库保存在单...

1 Referencing local array 2 The cost of copying elements 本文为摘录，原文为： https://www.cppstories.com/2023/initializer_list_improvements/ 1 Referencing local array std::initializer_list 在使用中会转化成为常量对象的匿名局部数组： std::initializer_list<int> wrong() { // for illustration only! return { 1, 2, 3, 4}; } int main() { std::initializer_list<int> x = wrong(); } The...

1 SCTP Associations 2 Using Multiple Interfaces 3 Streams 4 Association ID 5 Rec & Send 6 CDB with SCTP? 7 SCTP Interface Model 7.1 two types of SCTP sockets 7.2 The One-to-One Style 7.3 The One-to-Many Style 本文为摘录，原文为： https://www.linuxjournal.com/article/9749 1 SCTP Associations SCTP 的联合 (association) 类似于 TCP 的连接 (connection) ， 但又有不...

本文为摘录，原文为： attachments/pdf/c/p3346-gong.pdf

1 Introduction 1.1 Virtual IDs 1.2 Block-oriented and vectorized processing \\ 1.3 Late materialization 晚期物化 1.4 Column-specific compression 1.5 Direct operation on compressed data 1.6 Efficient join implementations 1.7 Redundant representation of individual columns in dif- ferent sort orders 1.8 Database cracking and adaptive indexing 1.9 Efficient loading architectures 2 Column-store internals and advanced techniques 2.1 Vectorized Processing 向量化处理 2.2 Compression 2.3 Operating...

1 Relfilenode of ordinary table 2 Relfilenode of Nail tables 3 Nail table Relfilenode storage mechanism 4 Summary 本文为摘录，原文为： https://www.highgo.ca/2021/01/12/the-mapping-of-oid-and-relfilenode-in-pg/ A table in PostgreSQL has a relfilenode value, which specifies the file name of the table on disk (except foreign table and partition table). In general, this value can be found in the relfilenode field of the pg_class table, but there...

1 什么是多版本并发控制？ 2 PostgreSQL 的多版本并发控制 2.1 多版本存储 2.2 Version Vacuum 3 为什么 PostgreSQL 的 MVCC 是最糟糕的 3.1 Problem #1: Version Copying 3.2 Problem #2: Table Bloat 3.3 Problem #3: Secondary Index Maintenance 3.4 Problem #4: Vacuum Management 4 Concluding Remarks 本文为...

1 ABSTRACT 2 BACKGROUND 2.1 Design Overview 3 DATA MODEL 3.1 Projections 3.2 Join Indexes 3.3 Prejoin Projections 3.4 Encoding and Compression 3.5 Partitioning 3.6 Segmentation: Cluster Distribution 3.7 Read and Write Optimized Stores 4 TUPLE MOVER 5 QUERY EXECUTION 5.1 Query Operators and Plan Format 5.2 Query Optimization 本文为摘录，原文为： attachments/pdf/3/The Vertica Analytic Database- C-Store 7 Years Later (p1790_andrewlamb_vldb2012).pdf 1 ABSTRACT...

1 展开 Bash 数组 (array) 时候， ${ARRARY[@]} 和 ${ARRARY[*]} 有什么区别？ 2 How do you escape characters in heredoc? 2.1 Question 2.2 Answer 3 special expansion: 4 will .bash_profile be sourced when executing scripts? 本文为摘录，原文为： https://unix.stackexchange.com/questions/505949/expanding-only-certain-variables-inside-a-heredoc 1 展开 Bash 数组 (array) 时候， ${ARRARY[@]} 和 ${ARRARY[*]} 有什么区...

1 Introduction 2 Related Work 2.1 Storage Layouts 2.2 Bit-(Un)Packing 3 SIMD-Friendly Bit-(Un)Packing 4 Composable Functions 5 Composable Compression Schemes 本文为摘录，原文为： attachments/pdf/a/Towards a New File Format for Big Data - SIMD-Friendly Composable Compression (2020-AzimAfroozeh).pdf 1 Introduction 2 Related Work 2.1 Storage Layouts 2.1.1 NSM 传统上，在数据库系统中，表格数据通...

1 INTRODUCTION 2 DESIGN AND METHODOLOGY 本文为摘录，原文为： attachments/pdf/6/p2613-guagliardo.pdf 1 INTRODUCTION NULL 用于表示不完整的数据 2 DESIGN AND METHODOLOGY

1 ABSTRACT 2 INTRODUCTION 本文为摘录，原文为： attachments/pdf/7/p3402-wang.pdf 1 ABSTRACT UDO: Universal Database Optimization, 通用数据库优化 为数据库的某种工作负载所做的特殊优化 包含多种调优：从索引选择到系统参数 基于强化学习 达...

1 ulimit 是做什么的 2 ulimit 从哪里读取配置文件 3 How PAM Modules related to /etc/security/limit.d/*.conf 本文为摘录，原文为： https://mydbops.wordpress.com/2017/12/10/ulimit-conflict-with-pam-and-systemd%E2%80%8B%E2%80%8B%E2%80%8B/#content 1 ulimit 是做什么的 User limits command, limit the use of system-wide resources. 2 ulimit 从哪里读取配置文件 从下面的文件、...