Tag: MySQL

Feed: Planet MySQL; Author: Kyle Hailey; Sure, wait event times in any database will include some CPU time, though ideally it should be minimal. Waits should be instrumented as close to the off CPU wait event as possible, i.e. if I’m doing an IO, then I want the wait to cover just the read call: start_wait('my_read_wait'); pread( ... ); end_wait('my_read_wait'); So my function that sets up the read will do some CPU that could get caught under the cover of the wait itself and the call to pread will use some CPU but most of the time should be ... Read More

Feed: Planet MySQL; Author: Frederic Descamps; When performing physical backup on system that are heavily used, it can happen that the backup speed cannot keep up with the redo log generation. This can happen when the backup storage is slower than the redo log storage media and this can lead in inconsistency in the generated backup. MySQL Enterprise Backup (aka MEB) and probably Percona Xtrabackup, benefit from the possibility to sequentially write redo log records to an archive file in addition to the redo log files. This feature was introduced in MySQL 8.0.17. How to enable it ? To enable ... Read More

Feed: Database Journal. Author: James Payne. There are many ways for a database administrator to learn how to use a database programming language, including a book or tutorial, such as the one you are reading now. Some people prefer that method and everyone learns differently. If you are the type of student that learns more in a classroom type of environment – and you want to learn MySQL as part of your database administrator or database developer training – we suggest you consider our list of the top online MySQL courses, as detailed in the sections below. Best MySQL Courses ... Read More

Feed: Planet MySQL; Author: HowToForge; Nginx (pronounced "engine x") is a free, open-source, high-performance HTTP server. Nginx is known for its stability, rich feature set, simple configuration, and low resource consumption. This tutorial shows how you can install Nginx on an Ubuntu 15.10 server with PHP support (through PHP-FPM) and MariaDB (as MySQL replacement). The term LEMP  stands for: Linux + Nginx + MySQL + PHP.   1 Preliminary Note In this tutorial, I will use the hostname server1.example.com with the IP address 192.168.1.100. These settings might differ for you, so you have to replace them where appropriate. 2 Installing MariaDB ... Read More

Feed: Planet MySQL; Author: Michael McLaughlin; +----+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | id | struct | +----+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | 1 | {"contact": [{"last_name": "Winn", "first_name": "Randi"}, {"last_name": "Winn", "first_name": "Brian"}], "account_number": "US00001"} | | 2 | {"contact": [{"last_name": "Vizquel", "first_name": "Oscar"}, {"last_name": "Vizquel", "first_name": "Doreen"}], "account_number": "US00002"} | | 3 | {"contact": [{"last_name": "Sweeney", "first_name": "Meaghan"}, {"last_name": "Sweeney", "first_name": "Matthew"}, {"last_name": "Sweeney", "first_name": "Ian"}], "account_number": "US00003"} | | 4 | {"contact": [{"last_name": "Clinton", "first_name": "Goeffrey"}], "account_number": "US00004"} | | 5 | {"contact": [{"last_name": "Moss", "first_name": "Wendy"}], "account_number": "US00005"} | | 6 | {"contact": [{"last_name": "Gretelz", "first_name": "Simon"}], "account_number": "US00006"} | | 7 | {"contact": [{"last_name": ... Read More

Feed: Planet MySQL; Author: Michael McLaughlin; Yesterday, I wrote a blog post that showed you how to write a query returning a JSON structure for a 1:many relationship. The relationship was between the member and contact table. It returns one account_number from the member table and a list of first_name and last_name columns from the contact table in a JSON structure. One of my students asked why I choose to strip the backslashes with Python, and my reply was the SQL was already complex for most blog readers. The student asked but how would you do it in SQL. OK, ... Read More

Feed: Planet MySQL; Author: Michael McLaughlin; Are they really tricks or simply basic techniques combined to create a solution. Before writing these mechanics for using native MySQL to create a compound JSON object, let me point out that the easiest way to get one is to use the MySQL Node.js library, as shown recently in my “Is SQL Programming” blog post. Moving data from a relational model output to a JSON structure isn’t as simple as a delimited list of columns in a SQL query. Let’s look at it in stages based on the MySQL Server 12.18.2 Functions that create ... Read More

Feed: Planet MySQL; Author: Kyle Hailey; JDBC Request: Cannot load JDBC driver class’com.mysql.jdbc.Driver’ solution June 22nd, 2022 Just  quick post to document an troublesome error when running Jmeter on Mysql Should be pretty simple, it’s just a question of putting the mysql-connector-java jar file, available at https://dev.mysql.com/downloads/connector/j/, into the classpath for Jmeter. The easiest way for me is to put this into the jmx file:       <stringProp name=“TestPlan.user_define_classpath”> /Users/kyle.hailey/jars/mysql-connector-java-8.0.29.jar,/home/ec2-user/jars/mysql-connector-java-8.0.29.jar</stringProp> Notice there is a space ” ” before the first jar file.  Apparently the space  was enough to cause the error. After removing the space , jmeter connected successfully to mysql. khaileyUncategorized ... Read More

Feed: Planet MySQL; Author: Oracle MySQL Group; High availability and replication is a must for any production environment in order to have a back-up process in place with minimum interruption in case of failure. In this article, I'll explain how to configure this architecture for MySQL HeatWave on OCI ... Read More

Feed: MariaDB Knowledge Base Article Feed. Author: . The following is a list of all function differences between MariaDB 10.10 and MySQL 8.0. It is based on functions available in the MySQL 8.0.24 and the MariaDB 10.10.0 releases. For a more complete list of differences, see Incompatibilities and Feature Differences Between MariaDB 10.10 and MySQL 8.0 Present in MariaDB Only Dynamic Columns Galera General Geographic MySQL has removed the following functions in MySQL 8.0. JSON Sequences Window Functions Miscellaneous Present in MySQL Only GTID MariaDB and MySQL have differing GTID implementations. GTID_SUBSET GTID_SUBTRACT WAIT_FOR_EXECUTED_GTID_SET WAIT_UNTIL_SQL_THREAD_AFTER_GTIDS Geographic MBRCOVEREDBY ST_BUFFER_STRATEGY ST_Collect ST_FrechetDistance ... Read More