Introduction As I explained in this article, multitenancy is an architectural pattern which allows you to isolate customers even if they are using the same hardware or software components. There are multiple ways you can achieve multitenancy, and in this article, we are going to see how you can implement a multitenancy architecture using the … Continue reading Hibernate database catalog multitenancy →
The post Hibernate database catalog multitenancy appeared first on Vlad Mihalcea.
You don’t need this tutorial if you have access to the
root user or another one with SUPER and
GRANT privileges.
The following instructions works for MySQL 5.7. You will need to
stop the MySQL server and start it with mysqld_safe
with the option skip-grant-tables:
sudo service mysql stop sudo mysqld_safe --skip-grant-tables & mysql -u root mysql
If you get an error on start, chances are there is no folder
created for the mysqld_safe executable to run, on my
tests I was able to solve by doing:
sudo mkdir /var/run/mysqld sudo chown -R mysql:mysql /var/run/mysqld
And then trying to start the mysqld_safe process
again.
After this, the MySQL console will pop up, and you need to set up
a new password for root. The second line is
necessary due to a MySQL bug # …
Dear MySQL users,
MySQL Connector/NET 6.10.8 is the fifth GA release with .NET
Core
now supporting various connection-string options and MySQL 8.0
server
features.
To download MySQL Connector/NET 6.10.8 GA, see the “Generally
Available
(GA) Releases” tab at
http://dev.mysql.com/downloads/connector/net/
Changes in Connector/NET 6.10.8 (2018-08-14, General Availability)
Functionality Added or Changed
* Optimistic locking for database-generated fields was
improved with the inclusion of the [ConcurrencyCheck,
DatabaseGenerated(DatabaseGeneratedOption.Computed)]
attribute. Thanks to Tony Ohagan for the patch. (Bug
#28095165, Bug #91064)
* All recent additions to .NET Core 2.0 now are compatible
with the Connector/NET 6.10 implementation.
* With the inclusion of the Functions.Like extended method,
scalar-function mapping, and …
Recently, we initiated a new project, the Open Source Database Community Blog. One way to think of this is as an online, year round version of the Percona Live conferences. If you have a story to tell, an experience to share, or a lesson to be learned send it along. As long as it’s related to open source database software, their management and application. That’s right. Not just Percona software. Any open source database software of all formats.
Unlike Percona Live, though, we are not limited by time or space. All submissions are welcome as long as they follow some simple guidelines.
We have already had some excellent posts, and in case this is news to you, here’s a recap:
This article is inspired by Percona blog post comparing MySQL 8.0 and
Percona Server 5.7 on IO-bound workload with Intel Optane
storage. There are several claims made by Vadim based on a single
test case, which is simply unfair. So, I'll try to clarify this
all based on more test results and more tech details..
But before we start, some intro :
InnoDB Parallel Flushing -- was introduced with MySQL 5.7
(as a single-thread flushing could no more follow), and implemented as
dedicated parallel threads (cleaners) which are involved in
background once per second to do LRU-driven flushing first (in
case there is no more or too low amount of free pages) and then
REDO-driven flushing (to flush …
MySQL 8.0 introduced a new feature that allows you to persist
configuration changes from inside MySQL. Previously you could
execute SET GLOBAL to change the configuration at
runtime, but you needed to update your MySQL configuration file
in order to persist the change. In MySQL 8.0 you can skip the
second step. This blog discuss how this works and how to backup
and restore the configuration.
Using SET PERSIST to set a variable and the persisted_variables table in the Performance Schema to get a list of persisted variables.Persisting Variables
You persist changes with either the SET PERSIST or
SET PERSIST_ONLY …
This may be a “duh” post for some, but I had to post this because I didn’t find the answer in typical places like stackoverflow when I had the issue. I recently worked on a project to expand database capacity by deploying new MySQL installations with memory, config, and disk space tweaks by backup/restore, replication topology change and, and failover. I did not notice that the old servers had “explicit_defaults_for_timestamp=OFF”. After restoring a binary backup and starting the replication thread on the new systems I got this error in the replication thread (column name in error corresponds to examples further down).
ERROR 1048 (23000): Column 'ts' cannot be null
Below, I will provide a synopsis to show statements that caused the error and why a simple global variable change fixed the issue. First, a sample table definition.
CREATE …[Read more]
Please join Percona’s Solution Engineer, Dimitri Vanoverbeke as he presents Amazon Migration Service: The Magic Wand to Migrate Away from Your Proprietary Environment to MySQL on Tuesday, August 14th, 2018 at 7:00 AM PDT (UTC-7) / 10:00 AM EDT (UTC-4).
In this talk, we will learn about the Amazon Migration Tool. The talk will cover the possibilities, potential pitfalls prior to migrating and a high-level overview of its functionalities.
[Read more]When you write programs that uses a database backend, it is necessary to use a connector/API to submit the queries and retrieve the result. If you are writing Python programs that used MySQL, you can use MySQL Connector/Python – the connector developered by Oracle Corporation.
Now there is a new book dedicated to the usage of the connector: MySQL Connector/Python Revealed, which is published by Apress. It is available in a softcover edition as well as an eBook (PDF, ePub, Mobi).
The book is divided into four parts spanning from the installation to error handling and troubleshooting. …
[Read more]In this post we will see a case study of a Galera Cluster migration to AWS Aurora and quick solution to the replication issue. A friend received an error in…
The post Galera cluster to AWS Aurora migration & HA_ERR_FOUND_DUPP_KEY first appeared on Change Is Inevitable.