Tag: SQL

Feed: R-bloggers. Author: Shige. The cyphr package seems to provide a good choice for small research group that shares sensitive data over internet (e.g., DropBox). I did some simple experiment myself and made sure it can actually serve my purpose. I did my experiment on two computers (using openssl): I created the test data on my Linux workstation running Manjaro then I tried to access the data on a Windows 7 laptop. For creating the data (Linux workstation): library(cyphr)# Create the test datadata_dir dir.create(data_dir)dir(data_dir)# Encrypt the test datacyphr::data_admin_init(data_dir)key filename cyphr::encrypt(saveRDS(iris, filename), key)dir(data_dir)# Cannot read the data with decrypting itreadRDS(filename)# Read ... Read More

Feed: R-bloggers. Author: Greg Wilson. We received almost 400 applications for our 2019 internship program from students with very diverse backgrounds. After interviewing several dozen people and making some very difficult decisions, we are pleased to announce that these twelve interns have accepted positions with us for this summer: Therese Anders: Calibrated Peer Review. Prototype tools to conduct experiments to see whether calibrated peer review is a useful and feasible feedback strategy in introductory data science classes and industry workshops. (mentor: Mine Çetinkaya-Rundel) Malcolm Barrett: R Markdown Enhancements. Tidy up and refactoring the R Markdown code base. (mentor: Rich Iannone) ... Read More

Feed: Planet MySQL; Author: MyDBOPS; It is very important for every DBA’s to backup their data frequently so that they can recover data if any problems occur such as Hardware failure, System crashes, Human mistakes. There are several ways to backup MySQL data. They are 1) Physical Backup 2) Logical Backup Physical Backup:               It is also called Raw Backup. It copies the directories and its files that has database contents. Logical Backup:             It is also called Text Backup. It converts all the available rows into single/multiple inserts and also contains create statements to create databases, tables, triggers and so on, ... Read More

Feed: Planet MySQL; Author: Frederic Descamps; On this article, I will show you how to migrate your wordpress database from the MariaDB on CentOS to the real MySQL. Why migrating to MySQL 8.0 ? MySQL 8.0 brings a lot of new features. These features make MySQL database much more secure (like new authentication, secure password policies and management, …) and fault tolerant (new data dictionary), more powerful (new redo log design, less contention, extreme scale out of InnoDB, …), better operation management (SQL Roles, instant add columns), many (but really many!) replication enhancements and native group replication… and finally many ... Read More

Feed: AWS for SAP. Author: Somckit Khemmanivanh. This post is by Santosh Choudhary, Senior Solution Architect at Amazon Web Services (AWS).AWS provides services and infrastructure to build reliable, fault-tolerant, and highly available systems in the cloud. Due to the business-critical importance of SAP Systems, high availability is essential to the business. High-availability for SAP applications can be achieved in many ways on AWS, depending on the operating system and database that you use. For example, SUSE High Availability Extensions (SUSE HAE), Red Hat Enterprise Linux for SAP with High Availability and Update Services (RHEL for SAP with HA and US), ... Read More

Feed: R-bloggers. Author: Bob Carpenter. First some background, then the bad news, and finally the good news. Spoiler alert: The bad news is that exploring the posterior is intractable; the good news is that we don’t need to explore all of it. Sampling to characterize the posterior There’s a misconception among Markov chain Monte Carlo (MCMC) practitioners that the purpose of sampling is to explore the posterior. For example, I’m writing up some reproducible notes on probability theory and statistics through sampling (in pseudocode with R implementations) and have just come to the point where I’ve introduced and implemented Metropolis ... Read More

Feed: Planet MySQL; Author: The Pythian Group; When designing a highly-available MySQL architecture, having a proxy to route the traffic to the appropriate instances is crucial to achieve transparent (or almost) failovers/switchovers. ProxySQL, a popular open source, SQL-level proxy is a great choice for this, and even though an experimental clustering feature is available, we could follow a simpler active-passive approach too, based on Common Address Redundancy Protocol (CARP), which will also provide a highly available IP for the applications to connect. Solution overview As mentioned before, this setup relies on a shared IP configured through CARP on the two ... Read More

Feed: Planet MySQL; Author: MySQL Performance Blog; PREVIOUS POST If you are using Galera replication, you know that schema changes may be a serious problem. With its current implementation, there is no way even a simple ALTER will be unobtrusive for live production traffic. It is a fact that with the default TOI alter method, Percona XtraDB Cluster (PXC) cluster suspends writes in order to execute the ALTER in the same order on all nodes. For factual data structure changes, we have to adapt to the limitations, and either plan for a maintenance window, or use pt-online-schema-change, where interruptions should ... Read More

Feed: Planet MySQL; Author: Tony Darnell; Adding a replicated MySQL database instance using a Group Replication server as the source March 25, 2019 Leave a comment You say you want a Replication? One of the best features of MySQL is the ability to use MySQL‘s built-in database replication feature to automatically replicate data from one server (source/master) to another (slave/replica). Group Replication was added in MySQL 5.7 as a way to provide a high-availability solution using a new variation of MySQL replication. (In some earlier posts, I explained how to setup Group Replication using three MySQL database servers and how to ... Read More

Feed: R-bloggers. Author: John Mount. As of cdata version 1.0.8 cdata implements an operator notation for data transform. The idea is simple, yet powerful. First let’s start with some data. d wrapr::build_frame( "id", "measure", "value" | 1 , "AUC" , 0.7 | 1 , "R2" , 0.4 | 2 , "AUC" , 0.8 | 2 , "R2" , 0.5 ) knitr::kable(d) 1 AUC 0.7 1 R2 0.4 2 AUC 0.8 2 R2 0.5 In the above data we have two measurements each for two individuals (individuals identified by the "id" column). Using cdata‘s new_record_spec() method we can capture a description ... Read More