We are glad to announce the release of the new version of Devart's MySQL GUI tool – dbForge Studio for MySQL v7.2!
In this blog post, I am going to show you how can you use Orchestrator and ProxySQL together.
In my previous blog post, I showed how to use bash scripts and move virtual IPs with Orchestrator. As in that post, I assume you already have Orchestrator working. If not, you can find the installation steps here.
In the case of a failover, Orchestrator changes the MySQL topology and promotes a new master. But who lets the application know about this change? This is where ProxySQL helps us.
ProxySQL
You can find the ProxySQL install steps …
[Read more]In a previous post, I explained the architecture and design for the transactional data dictionary in MySQL 8.0. In this post I intend to summarize the status of this work in the 8.0.0 Milestone Release.
Storing all dictionary information in InnoDB tables
The MySQL 8.0.0 now stores dictionary data in InnoDB tables. …
This post introduces PyMyTools v0.1: my first version of a simple
diagnostic toolkit for automating boring DBA tasks. Read on for
tool descriptions and demonstrations!
Introduction No lengthy introductions this time:
- I wrote these tools to make my own everyday tasks less time consuming. I hope you too will find them useful.
- Tools can be downloaded from GitHub and are provided under the MIT License.
- Your feedback is very welcome (use GitHub Issues).
Tools: general description The tools are designed to automate some of the simple DBA tasks:
- Monitor the values of server status variables.
- Report on basic status variables (buffer/cache usage, uptime, query traffic).
- Dump …
In this blog post, we will discuss how we can verify if an application transaction executed on the master has been applied to the slaves.
In summary, is a good practice to alleviate the load on the master by doing reads on slaves. It is acceptable in most of the cases to just connect on slaves and issue selects. But there are some cases we need to ensure that the data we just applied on our master has been applied on the slaves before we query it.
One way to do this is using a built-in function called MASTER_POS_WAIT. This function receives a binary log name and position. It will block the query until the slave applies transactions up to that point, or timeout. Here is one example of how to use it:
-- insert our data on master master [localhost] {msandbox} (test) > INSERT INTO test VALUES …[Read more]
Since MySQL now can be used on Oracle Cloud, you will be able to experience a more secure, cost-effective and enterprise-level database applications using MySQL.
The post Oracle MySQL Cloud Service appeared first on Datavail.
This blog gives some background to the decisions made when
designing the
storage engine NDB Cluster used in MySQL Cluster around how to
support
real-time requirements (or as I sometime refer to it, predictable
response
time requirements).
Requirement analysisWhen analysing the requirements for NDB
Cluster based on its usage in telecom
databases two things were important. The first requirement is
that we need to
be able to respond to queries within a few milliseconds (today
even down to
tens of microseconds). The second requirement is that we need to
do this while
at the same time supporting a mix of simple traffic queries
combined with a
number of more complex queries running at the same time.
The first requirement was the main requirement that led to NDB
Cluster using a
main memory storage model with durability on disk using a REDO
log and
various …
This is a description of the simplest case of 2-phase commit (2PC) in NDBCluster: one transaction, containing a single insert, update or delete operation on a single row. The PREPARE phase of the 2PC is initiated by the API node (which is a mysqld or a NoSQL client) sending a TCKEYREQ to the Transaction Coordinator of a data node.…
We regularly get questions about how to set up a Galera cluster with just 2 nodes. The documentation clearly states you should have at least 3 Galera nodes to avoid network partitioning. But there are some valid reasons for considering a 2 node deployment, e.g., if you want achieve database high availability but have limited budget to spend on a third database node. Or perhaps you are running Galera in a development/sandbox environment and prefer a minimal setup.
Galera implements a quorum-based algorithm to select a primary component through which it enforces consistency. The primary component needs to have a majority of votes, so in a 2 node system, there would be no majority resulting in split brain. Fortunately, it is possible to add a …
[Read more]In this blog, we’ll discuss changing the tablespace directory using pt-online-schema-change.
One of the most annoying situations in the life of a DBA is realizing that the disk where the datadir resides is running out of space. If you’re lucky enough to run over an LVM volume or a RAID (depending on the level, though), it is easy to add disk space. But what if you are not that lucky, and your datadir is running on a single disk? Not so funny!
That is the exact situation we recently faced with a customer, for both the master and slave server. When trying to figure out a solution we saw that:
- There was enough space on a different partition within the same server.
- The tables have their own tablespace (innodb_file_per_table = on)
- The MySQL version was …