Querying or Reading Data OpenTSDB offers a number of means to extract data such as CLI tools, an HTTP API and as a GnuPlot graph. Querying with OpenTSDB's tag based system can be a bit tricky so read through this document and checkout the following p…

这个报错网上搜索了一下,大部分是由于MySQL意外关闭或强制重启造成的binlog文件事务点读取异常造成的主从同步报错 Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: 'binlog truncated in the middle of event; consider out of disk space on master; the last event was read fro…

Querying and Inserting Data Simple Query Partition Based Query Joins Aggregations Multi Table/File Inserts Dynamic-Partition Insert Inserting into Local Files Sampling Union All Array Operations Map (Associative Arrays) Operations Custom Map/Reduce S…

本地MySQL环境,是两台MySQL做M-M复制.今天发现错误信息: mysql 5.5.28-log> show slave status\G *************************** 1. row ***************************                Slave_IO_State:                   Master_Host: 88.88.88.88                   Master_User: replicate…

mysql> show slave status\G *************************** 1. row ***************************                Slave_IO_State:                    Master_Host: 10.122.41.208                   Master_User: replication                   Master_Port: 3306    …

/*Author: Jiangong SUN*/ As I've manipulated a lot of data using SQL data reader in recent project. And people says it's not good to access the data by column name. So I've made an performance test in reading data from SQL data reader. Firstly, I've…

从库报这个错误:Got fatal error 1236 from master when reading data from binary log: 'Could not find first log file name in binary log index file' Got fatal error 1236 from master when reading data from binary log: 'could not find next log' 可以 stop slave; res…

年后回来查看mysql运行状况与备份情况,登录mysql从库查看主从同步状态 mysql> show slave status\G; *************************** . row *************************** Slave_IO_State: Master_Host: 101.200.*.* Master_User: backup Master_Port: Connect_Retry: Master_Log_File: master-bin. Rea…

1:停止slave服务器的主从同步 stop slave; 2:对Master数据库加锁 flush tables with read lock; 3:备份Master上的数据 mysqldump -uroot -p -B db1 db2 >bak.sql 4:重置Master服务 reset master; reset master 将删除所有的二进制日志,创建一个名为  ****.000001的空日志文件.reset master 并不会影响slave服务器的工作状态.盲目执行这个命令有可能…

刚处理完“挖矿”事件,在做最后一个MySQL NBU备份的时候,发现从库有问题,好奇的是怎么主从状态异常没有告警呢?先不管这么多了,处理了这个问题再完善告警内容. 一.错误信息 从库show slave status \G看到的错误信息如下: Slave_IO_Running: No Slave_SQL_Running: Yes Last_IO_Errno: Last_IO_Error: Got fatal error ' at 4.' 二.错误原因 这里看到从库的io_thread已经终止,错…

setup slave from backup i got error Got fatal error 1236 from master when reading data from binary log: 'Could not find first log file name in binary log index file' MASTER MariaDB [(none)]> SHOW BINLOG EVENTS IN 'mysqld-bin.140180' FROM 101070557 LI…

小伙伴儿们有福啦,2015年4月10日,Hadley Wickham大牛(开发了著名的ggplots包和plyr包等)和RStudio小组又出新作啦,新作品readr包和readxl包分别用于R读取text数据和Excel电子表格数据.事实上,R已经有了一堆读取数据的函数,比如read.table家族以及其巨多的变形,那么为了牛牛们为什么还要开发这两个包呢?原因很简单,这两个包的读取速度比R内置数据读入函数更快!!!记住哦,是快很多哈!不信,我们下来试试就知道啦!哈哈!平时读取小数据的童鞋可能不…

在source那边,执行: flush logs;show master status; 记下File, Position. 在target端,执行: CHANGE MASTER TO MASTER_LOG_FILE='testdbbinlog.000008',MASTER_LOG_POS=107;slave start;show slave status \G 一切正常. 参考:https://blog.csdn.net/edwzhang/article/details/17226975---…

reset slave会清除从库的所有复制信息.一般应用场景:如切换为不同的Master, 主从重做等: 1. 命令在slave上执行,执行前一定要stop slave. 2. 执行reset slave后,会清除复制相关的所有信息,包括:master.info, relay-log.info, 及无条件删除所有的中继日志(relay logs). 注意是无条件的,也就是不管理你Slave SQL线程是否把所有的relay log重放完了. 3. 注意,stop slave后,先保存show s…

首先遇到这个是因为binlog位置索引处的问题,不要reset slave: reset slave会将主从同步的文件以及位置恢复到初始状态,一开始没有数据还好,有数据的话,相当于重新开始同步,可能会出现一些问题: 一般做主从同步,都是要求以后的数据实现主从同步,而对于旧的数据完全可以使用数据库同步工具先将数据库同步,完了再进行主从同步: 好了遇到上面的问题,正确做法是: 1.打开主服务器,进入mysql 2.执行flush logs://这时主服务器会重新创建一个binlog文件: 3.在主服…

Writing Data You may want to jump right in and start throwing data into your TSD, but to really take advantage of OpenTSDB's power and flexibility, you may want to pause and think about your naming schema. After you've done that, you can procede to p…

opentsdb 概览(overview) opentsdb 存储细节(Writing) rowkey的设计 rowkey的具体实现 压缩(compaction) 追加模式(appends) opentsdb UID的分配(UID Assignment) opentsdb 查询细节(Reading) rowkey中加salt的情况(Salting) 其他配置(Configuration) http接口(HTTP API) opentsdb连接Kerberos认证的HBase(非重点,仅顺手记录于…

#ifndef _BYTEBUFFER_H #define _BYTEBUFFER_H #include <msgpack.hpp> typedef unsigned char uint8; /* Unsigned 8 bit quantity */ typedef signed char int8; /* Signed 8 bit quantity */ typedef unsigned short uint16; /* Unsigned 16 bit quantity */ typedef…

Are you a interested in taking a course with us? Learn about our programs or contact us at hello@zipfianacademy.com. There are plenty of articles and discussions on the web about what data science is, what qualitiesdefine a data scientist, how to nur…

Recently we were building a Shiny App in which we had to load data from a very large dataframe. It was directly impacting the app initialization time, so we had to look into different ways of reading data from files to R (in our case customer provide…

文章标题 Introducing DataFrames in Apache Spark for Large Scale Data Science 一个用于大规模数据科学的API——DataFrame 作者介绍 Reynold Xin, Michael Armbrust and Davies Liu 文章正文 Today, we are excited to announce a new DataFrame API designed to make big data processing even…

每次出错的都是和posix相关先把结论说了: fn_ofd_w和fn_ofd_r的SAFE_FCNTL参数F_OFD_SETLKW fn_posix_w和fn_posix_r的SAFE_FCNTL参数F_SETLKW 四个函数都用的flock64结构体 case F_SETLK: case F_SETLKW: err = get_compat_flock(&flock, compat_ptr(arg)); case F_SETLK64: case F_SETLKW64: case F_OFD_S…

Efficient data transfer through zero copy https://www.ibm.com/developerworks/library/j-zerocopy/ Efficient data transfer through zero copy Zero copy, zero overhead Sathish K. Palaniappan and Pramod B. NagarajaPublished on September 02, 2008 FacebookT…

https://hadoop.apache.org/docs/r2.7.2/hadoop-project-dist/hadoop-hdfs/HdfsDesign.html Introduction [相对于POSIX,放宽要求] The Hadoop Distributed File System (HDFS) is a distributed file system designed to run on commodity hardware. It has many similarities…

https://hadoop.apache.org/docs/r1.2.1/hdfs_design.html Introduction The Hadoop Distributed File System (HDFS) is a distributed file system designed to run on commodity hardware. It has many similarities with existing distributed file systems. However…

Reading Data There are a few principal functions reading data into R. read.table, read.csv, for reading tabular data readLines, for reading lines of a text file source, for reading in R code files (inverse of dump) dget, for reading in R code files (…

A text file is a sequence of characters stored on a permanent medium like a hard drive, flash memory, or CD-ROM. To read a file, you can use open to create a file object: Mode ‘r’ means that file is open for reading. The file object provides several…

https://docs.microsoft.com/en-us/aspnet/web-forms/overview/getting-started/getting-started-with-aspnet-45-web-forms/create_the_data_access_layer This tutorial describes how to create, access, and review data from a database using ASP.NET Web Forms an…

使用的uboot版本是1.1.6,是打过u-boot-1.1.6_jz2440.patch的: kernel使用的版本是3.4.2, 也是打过linux-3.4.2_camera_jz2440.patch的: u-boot-1.1.6编译步骤如下(开发环境ubuntu16.04): 1. 添加环境变量 vim /etc/profile export PATH=/usr/local/gcc-3.4.5-glibc-2.3.6/bin:$PATH 这里需要注意的是u-boot-1.1.6版本使用gc…

Segregate operations that read data from operations that update data by using separate interfaces. This pattern can maximize performance, scalability, and security; support evolution of the system over time through higher flexibility; and prevent upd…