作者：XuYuchong 1、创建数据表 1.1、创建shard普通表 说明： distribute by shard(x) 用于指定分布键，数据分布于那个节点就是根据这个字段值来计算分片。 to group xxx 用于指定存储组（每个存储组可以有多个节点）。 分布键字段值不能修改，字段长度不能修改，字段类型不能修改。 1.2、创建shard普通分区表 [tbase@VM_0_37_centosshell]$psql-h172.16.... ...继续阅读 (8)

作者：XuYuchong 1，环境变量配置 /etc/profile exportJAVA_HOME=/opt/jdk1.8.0_40 exportCLASSPATH=:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar exportHADOOP_HOME=/opt/hadoop-3.3.0 exportPATH=$PATH:$JAVA_HOME/bin exportPATH=$PATH:/opt/hadoop-3.3.0/bin/:/op... ...继续阅读 (9)

作者：XuYuchong 1，系统环境变量配置 exportJAVA_HOME=/opt/jdk1.8.0_40 exportHADOOP_HOME=/opt/hadoop-3.3.0 exportPATH=$PATH:$JAVA_HOME/bin exportPATH=$PATH:/opt/hadoop-3.3.0/bin/:/opt/hadoop-3.3.0/sbin 2，配置hadoop，使用hadoop用户 //本次测试使用了，单节点，伪分布式模式，搭建HDFS文件系统，用... ...继续阅读 (5)

作者：崔鹏 目录 执行计划 成本计算 索引概述 Auto_explain 目标 1.explian SQL分析工具的使用, 理解explain 的代价计算原理. 2.掌握explain 输出的含义 (如 组合行集 , 节点处理 , 合并连接, 哈希连接) EXPLAIN EXPLAIN [ ( option [, ...] ) ] statement n EXPLAIN [ ANALYZE ] [ VERBOSE ] statement ANALYZE [ boolean ...继续阅读 (15)

作者：XuYuchong 软件架构: 环境基础信息: etcd 192.168.5.220 2379 postgres0 192.168.0.200 5432 master postgres1 192.168.0.220 5432 ...继续阅读 (3)

作者：崔鹏 目录 1.进程架构的概述 2.内存架构的概述 3.核心进程简介 4.核心进程源码浅析 进程架构概述1 – 体系架构概览 记忆方法：3 + 5 + 8 + 5 进程架构概述2 Backend Processes概述 后端进程，也称为postgres，由 postgres 服务器进程启动并处理由一个连接的客户端发出的所有语句。 它通过单个 TCP 连接与客户端通信，并在客户端断开连接时终止。 由于只允许操作一个数据... ...继续阅读 (8)

原创崔鹏 点击上方蓝色文字关注我们 讲述PostgreSQL的"内功",帮助大家打牢基础。 快速从初级DBA晋级到中高级DBA,作者认为学习技术和练习武功有异曲同工之妙。 "内功"练习到"登峰造极的境界"飞花摘叶皆可伤人,学习技术依然如此。 课程目录 /CONTENT 1.Database Cluster Table 2.进程与内存架构 3.查询相关 4.FDW 5.并发控制 6.VACUUM 7.HOT 8.Buffer Manager 9.WAL 10.PI. ...继续阅读 (16)

作者：XuYuchong 软件版本： PostgreSQL 13.4 repmgr 5.3 数据库安装规划： node_id node_name port data_directory 1 node1 5432 /data/n001 primary 2 node2 ...继续阅读 (4)

目前国内分布式数据库背景： 1.数据爆发增长：大数据时代，万物互联，业务数据量爆发增长，传统服务器读、写、存储，等遇到多方面压力过大。 2. 扩展时效性：传统数据库进行高性能硬件的升级扩展时，进行数据迁移过程中需要充分考虑数据完整性、可用性以及切换上线调试时效性等对业务的影响。 3. 冷热数据混合：热点数据集中访问导致系统的 CPU，内存，I/O读写短时间无法承受，服务器负载过大，响应延迟。 4. 运行维护：大多为了降低延迟和响应时间，提高数据检索效率，采用中间件进行分库分表，需要手动维 ...继续阅读 (15)

崔鹏老师上周技术分享课 精华讲解 内容简介 1.Write-Ahead Logging概览 2.Transaction log 3.FPI 4.WAL文件与记录的内部结构 5.事务日志文件管理 6.实例恢复 7.归档 8.WAL写放大浅析 9.walminer、pg_waldump、wal2json工具浅析 Write-Ahead Logging概览 作用 故障中,保证数据不丢失 Point-in-Time Recovery PITR Streaming Replica.. ...继续阅读 (13)

2021年10月23日，崔鹏老师受邀参加PG社区举办的数据库人才与业务生态应用专题讲座，作为本次受邀嘉宾，崔老师将带大家了解PGHA 关于专网通信领域的研究。崔老师同时也是首批获得PGCM认证的大师，PG ACE伙伴，中国PG分会官方认证讲师。相信会给大家带来不一样的新知识。 除了此次论坛，崔老师还受邀参加了1024程序员节年度科技盛宴，与众多大咖一起讨论互联网的未来，地址在长沙科技园。感兴趣的小伙伴可以看看。 附上： 附上： ... ...继续阅读 (7)

作者：崔鹏 内容解释 pg_control version number: 是控制文件版本号。 Catalog version number: 是系统表版本号，格式是yyyymmddN。 Database system identifier: 数据库系统号 这个标识串是一个64bit的整数。 Database cluster state: 记录实例的状态。源码文件中看到数据库的几种状态： starting up：表示数据库正在启动状态。 shut down： 数据库实例（非Standby） ...继续阅读 (11)

2021-10-09 16:52·云贝教育 作者：胖墩老师 走向大神的第一步 国产数据库广泛基于PostgreSQL进行产品 开发。当前中国PostgreSQL就业市场主要 由传统数据库厂商、云厂商、应用软件开发 商、技术服务商、服务器厂商、咨询公司、 最终用户等组成。根据多家头部IT企业给出 的数据参考，PostgreSQL相关岗位需求正 在以70-150%的速度增长。PostgreSQL产 业形势的巨大发展变革，致使人才存量和行 业应用需求之间产生了明显差距。 Postg ...继续阅读 (4)

作者：胖墩老师 MySQL的监控通过日志文件来实现。 那么MySQL的日志文件有哪些类型呢？MySQL使用以下这几种类型的日志来记录服务器活动信息。 Error log错误日志:关于启动、关闭和异常情况的诊断消息（排查错误） General query log通用查询日志:服务器从客户端接收到的所有语句（全局监控） Slow query log慢速查询日志:执行时间较长的查询（性能优化） Audit log审计日志:针对企业版的策略审计(主从搭配) Binary log二进制日志:用于. ...继续阅读 (8)

作者：胖墩老师 Redo log（重做日志） 定义：在它们被制成数据文件之前，存储这些修改操作。优点：这使得InnoDB可以优化数据写操作，这样它们就不需要同步进行 用于：在崩溃恢复期间使用，InnoDB会在重做日志文件中重做操作，即使是那些在崩溃前没有写入数据文件的操作，这样以确保所有表的事务一致性 位置：默认位于数据目录中 用the innodb_log_group_home_dir option（选项）进行控制。 Undo log（撤回日志） 定义：存储被事务修改的未修改数据 ...继续阅读 (5)

作者：泡杯长岛冰茶 nginx 安装配置 1. nginx 安装 [root@localhost ~]# yum module list nginx Updating Subscription Management repositories. Unable to read consumer identity Last metadata expiration check:0:06:10 ago on Mon20Sep202108:05:59 PM CST. local_AppSt... ...继续阅读 (10)

作者：泡杯长岛冰茶 Linux 8 web apache 配置 1.1. 配置网络 [root@localhost ~]# nmcli device status DEVICE TYPE STATE CONNECTION ens192 ethernet connected -- virbr0 bridge connected (externally) virbr0 ... ...继续阅读 (7)

作者：泡杯长岛冰茶 1.快照管理 虚拟机快照功能概述；快照是相当于虚拟机备份，当我们在虚拟机上做某些测试失败时，可以迅速地还原当初的状态，便于重新实验测试。 1.1 创建虚拟机快照 a)打开VMware Workstation pro点击虚拟机->快照->拍摄快照 b)名称栏输入名称（输入一个有意义的名称，便于区分） c)点击快照管理 d)点击快照获取快照信息 1.2.还原快照 a)点击需要还的快照 快照管理菜单栏里找到快照管理 下图... ...继续阅读 (6)

空间恢复开放日dzh.mop.com/topic/596136dzh.mop.com/topic/596128dzh.mop.com/topic/593932dzh.mop.com/topic/593318dzh.mop.com/topic/593222dzh.mop.com/topic/593210dzh.mop.com/topic/593188dzh.mop.com/topic/593184dzh.mop.com/topic/592358dzh.mop.com/topic/592357dzh.mop.com/topic/592354dzh.mop.com/topic/592352dzh.mop.com/topic/589406dzh.mop.com/topic/589360dzh.mop.com/topic/589358dzh.mop.com/topic/589354dzh.mop.com/topic/589352dzh.mop.com/topic/588752dzh.mop.com/topic/588749dzh.mop.com/topic/588748dzh.mop.com/topic/588747dzh.mop.com/topic/588745dzh.mop.com/topic/588744dzh.mop.com/topic/588743dzh.mop.com/topic ...继续阅读 (23)

离开的房间了快速的记录rdzh.mop.com/topic/1127540dzh.mop.com/topic/1176654dzh.mop.com/topic/1123422dzh.mop.com/topic/1176630dzh.mop.com/topic/1126268dzh.mop.com/topic/1123608dzh.mop.com/topic/1128242dzh.mop.com/topic/1123600dzh.mop.com/topic/1126267dzh.mop.com/topic/1177678dzh.mop.com/topic/1127990dzh.mop.com/topic/1129773dzh.mop.com/topic/1125524dzh.mop.com/topic/1126331dzh.mop.com/topic/1176629dzh.mop.com/topic/1125705dzh.mop.com/topic/1139184dzh.mop.com/topic/1124168dzh.mop.com/topic/1125853dzh.mop.com/topic/1125876dzh.mop.com/topic/1125914dzh.mop.com/topic/1123966dzh.mop.com/topic/1125517dzh.mop.com/t ...继续阅读 (20)

圣诞节开发商贷款方式打开dzh.mop.com/topic/1123390dzh.mop.com/topic/1123546dzh.mop.com/topic/1124195dzh.mop.com/topic/1123567dzh.mop.com/topic/1124157dzh.mop.com/topic/1123571dzh.mop.com/topic/1123501dzh.mop.com/topic/1124191dzh.mop.com/topic/1123725dzh.mop.com/topic/1123524dzh.mop.com/topic/1123667dzh.mop.com/topic/1124155dzh.mop.com/topic/1124194dzh.mop.com/topic/1123469dzh.mop.com/topic/1123914dzh.mop.com/topic/1123021dzh.mop.com/topic/1124172dzh.mop.com/topic/1124510dzh.mop.com/topic/1123910dzh.mop.com/topic/1123955dzh.mop.com/topic/1124731dzh.mop.com/topic/1124197dzh.mop.com/topic/1123891dzh.mop.com/t ...继续阅读 (18)

是对方可接受的了困扰dzh.mop.com/topic/1123059dzh.mop.com/topic/1122490dzh.mop.com/topic/1122129dzh.mop.com/topic/1122957dzh.mop.com/topic/1122923dzh.mop.com/topic/1122840dzh.mop.com/topic/1123006dzh.mop.com/topic/1122861dzh.mop.com/topic/1123092dzh.mop.com/topic/1123064dzh.mop.com/topic/1123054dzh.mop.com/topic/1123015dzh.mop.com/topic/1123007dzh.mop.com/topic/1122762dzh.mop.com/topic/1123112dzh.mop.com/topic/1123088dzh.mop.com/topic/1123118dzh.mop.com/topic/1122053dzh.mop.com/topic/1122245dzh.mop.com/topic/1122979dzh.mop.com/topic/1123123dzh.mop.com/topic/1122863dzh.mop.com/topic/1123106dzh.mop.com/top ...继续阅读 (33)

双方都是可分解落实到dzh.mop.com/topic/1122193dzh.mop.com/topic/1122156dzh.mop.com/topic/1122258dzh.mop.com/topic/1122303dzh.mop.com/topic/1122176dzh.mop.com/topic/1122210dzh.mop.com/topic/1121996dzh.mop.com/topic/1122290dzh.mop.com/topic/1121904dzh.mop.com/topic/1122212dzh.mop.com/topic/1121999dzh.mop.com/topic/1122191dzh.mop.com/topic/1122066dzh.mop.com/topic/1122127dzh.mop.com/topic/1122067dzh.mop.com/topic/1122042dzh.mop.com/topic/1122087dzh.mop.com/topic/1121906dzh.mop.com/topic/1121863dzh.mop.com/topic/1122216dzh.mop.com/topic/1122301dzh.mop.com/topic/1122264dzh.mop.com/topic/1122099dzh.mop.com/top ...继续阅读 (17)

dsfdshrkdzh.mop.com/topic/1092866dzh.mop.com/topic/609249dzh.mop.com/topic/135027dzh.mop.com/topic/1092877dzh.mop.com/topic/591444dzh.mop.com/topic/587471dzh.mop.com/topic/134308dzh.mop.com/topic/1226275dzh.mop.com/topic/1190066dzh.mop.com/topic/1103019dzh.mop.com/topic/584583dzh.mop.com/topic/5198dzh.mop.com/topic/714533dzh.mop.com/topic/1233060dzh.mop.com/topic/1212140dzh.mop.com/topic/481686dzh.mop.com/topic/1105211dzh.mop.com/topic/277794dzh.mop.com/topic/673847dzh.mop.com/topic/599688dzh.mop.com/topic/149608dzh.mop.com/topic/1187786dzh.mop.com/topic/3261dzh.mop.com/topic/584568dzh.mop.com ...继续阅读 (15)

看到是否记录反馈时间老人dzh.mop.com/topic/607092dzh.mop.com/topic/609453dzh.mop.com/topic/584550dzh.mop.com/topic/627386dzh.mop.com/topic/832382dzh.mop.com/topic/613323dzh.mop.com/topic/1085765dzh.mop.com/topic/622185dzh.mop.com/topic/837031dzh.mop.com/topic/628572dzh.mop.com/topic/626689dzh.mop.com/topic/748144dzh.mop.com/topic/725385dzh.mop.com/topic/1095079dzh.mop.com/topic/725219dzh.mop.com/topic/1079724dzh.mop.com/topic/832369dzh.mop.com/topic/1093473dzh.mop.com/topic/1085650dzh.mop.com/topic/616487dzh.mop.com/topic/676524dzh.mop.com/topic/626629dzh.mop.com/topic/732530dzh.mop.com/topic/135877dzh.mop ...继续阅读 (8)

接口上飞机开始的好客人dzh.mop.com/topic/607092dzh.mop.com/topic/609453dzh.mop.com/topic/584550dzh.mop.com/topic/627386dzh.mop.com/topic/832382dzh.mop.com/topic/613323dzh.mop.com/topic/1085765dzh.mop.com/topic/622185dzh.mop.com/topic/837031dzh.mop.com/topic/628572dzh.mop.com/topic/626689dzh.mop.com/topic/748144dzh.mop.com/topic/725385dzh.mop.com/topic/1095079dzh.mop.com/topic/725219dzh.mop.com/topic/1079724dzh.mop.com/topic/832369dzh.mop.com/topic/1093473dzh.mop.com/topic/1085650dzh.mop.com/topic/616487dzh.mop.com/topic/676524dzh.mop.com/topic/626629dzh.mop.com/topic/732530dzh.mop.com/topic/135877dzh.mop. ...继续阅读 (12)

但是客服经理是打开了dzh.mop.com/topic/612288dzh.mop.com/topic/611679dzh.mop.com/topic/612292dzh.mop.com/topic/610961dzh.mop.com/topic/598077dzh.mop.com/topic/599582dzh.mop.com/topic/161197dzh.mop.com/topic/1221157dzh.mop.com/topic/600958dzh.mop.com/topic/610967dzh.mop.com/topic/596390dzh.mop.com/topic/603185dzh.mop.com/topic/596533dzh.mop.com/topic/597031dzh.mop.com/topic/598152dzh.mop.com/topic/1226906dzh.mop.com/topic/604009dzh.mop.com/topic/599579dzh.mop.com/topic/159747dzh.mop.com/topic/601474dzh.mop.com/topic/596777dzh.mop.com/topic/589190dzh.mop.com/topic/143882dzh.mop.com/topic/289747dzh.mop.com/ ...继续阅读 (9)

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圣诞节快发货快速的健康dzh.mop.com/topic/613334dzh.mop.com/topic/613331dzh.mop.com/topic/613330dzh.mop.com/topic/613324dzh.mop.com/topic/613311dzh.mop.com/topic/613292dzh.mop.com/topic/613285dzh.mop.com/topic/613279dzh.mop.com/topic/612886dzh.mop.com/topic/612622dzh.mop.com/topic/612618dzh.mop.com/topic/612596dzh.mop.com/topic/612569dzh.mop.com/topic/612567dzh.mop.com/topic/612565dzh.mop.com/topic/612553dzh.mop.com/topic/612550dzh.mop.com/topic/612511dzh.mop.com/topic/612509dzh.mop.com/topic/612488dzh.mop.com/topic/612467dzh.mop.com/topic/612466dzh.mop.com/topic/612463dzh.mop.com/topic/612454dzh.mop.com/t ...继续阅读 (11)

奥斯卡的记录萨克dzh.mop.com/topic/620034dzh.mop.com/topic/620033dzh.mop.com/topic/620032dzh.mop.com/topic/620028dzh.mop.com/topic/620026dzh.mop.com/topic/619863dzh.mop.com/topic/619433dzh.mop.com/topic/619428dzh.mop.com/topic/619427dzh.mop.com/topic/619424dzh.mop.com/topic/619418dzh.mop.com/topic/619413dzh.mop.com/topic/619412dzh.mop.com/topic/619410dzh.mop.com/topic/619408dzh.mop.com/topic/619405dzh.mop.com/topic/619404dzh.mop.com/topic/619401dzh.mop.com/topic/619385dzh.mop.com/topic/619383dzh.mop.com/topic/619376dzh.mop.com/topic/619364dzh.mop.com/topic/619242dzh.mop.com/topic/618969dzh.mop.com/topi ...继续阅读 (13)