This is old news for MySQL/MariaDB expert but people that are starting using InnoDB do not always know that disk space is not automatically released when deleting data from a table.  To explain and demonstrate that, I will take two real-world examples: table1 and table2.

Recently, more than 90% and about 20% of rows were deleted from table1 and table2 (those tables contain real data, I only

Introduction:

• MySQL 5.7 introduces a new feature called virtual/generated column. It is called generated column because the data of this column is computed based on a predefined expression or from other columns.

What is Virtual Column ?

• In general virtual columns appear to be normal table columns, but their values are derived rather than being stored on disk.
• Virtual columns are one of the top features in MySQL 5.7,they can store a value that is derived from one or several other fields in the same table in a new field.

Syntax :

Syntax for adding new virtual column,

==> Alter table table_name add column column_name generated always as column_name virtual;

Example :

Alter table contacts add column generated always as mydbops_test virtual / stored.

GENERATED ALWAYS …

I regularly meet with MySQL customers and I'm still a little surprised to see critical applications running on "not really" recent versions (to put it mildly) :)

The good news is that obviously old versions of MySQL are sufficiently stable and powerful to run the modern business. However, even if I understand that it is sometimes appropriate to freeze all layers of an architecture, it is often a shame not to take advantage of the latest improvements from a performance, stability, security point of view and obviously for the new features that the latest GA provides :

Introduction As previously explained, CDC (Change Data Capture) is one of the best ways to interconnect an OLTP database system with other systems like Data Warehouse, Caches, Spark or Hadoop. Debezium is an open source project developed by Red Hat which aims to simplify this process by allowing you to extract changes from various database … Continue reading How to extract change data events from MySQL to Kafka using Debezium →

As you may know by now, MySQL 8.0.2 DMR is out ! \o/

Many features have been added (see Geir Høydalsvik‘s announcement) and of course the replication also brought new features and improvements (see this post from Luís Soares).

But some improvements in the monitoring broke the added sys view used by ProxySQL to monitor the state of a member of the group:

mysql> select * from sys.gr_member_routing_candidate_status;
+------------------+-----------+---------------------+----------------------+
| viable_candidate | read_only | transactions_behind | transactions_to_cert | …

The MariaDB project is pleased to announce the immediate availability of MariaDB 5.5.57. This is a stable (GA) release. See the release notes and changelog for details. Download MariaDB 5.5.57 Release Notes Changelog What is MariaDB 5.5? MariaDB APT and YUM Repository Configuration Generator Thanks, and enjoy MariaDB!

The post MariaDB 5.5.57 now available appeared first on MariaDB.org.

Ramesh,
It looks to me like the problem is related MHA can’t connect to that servers. Are you sure the MHA DB user can connect to that server from the MHA manager?
If you are using different settings than the defaults, like datadir, port, … etc. you should specify that in the MHA configs as well.

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1. Watch the parentheses. It’s:

ST_GeomFromText('POLYGON((outerRing), (innerRing), (innerRing), ...)')

The inner rings are optional. If you have just the outer ring, then it’s still:

ST_GeomFromText('POLYGON((outerRing))')

and not:

ST_GeomFromText('POLYGON(outerRing)')

2. Polygons have to start and end at the same point.

3. Watch the commas. Rings are comma-delimited sets of of whitespace-delimited coordinate pairs:

x1 y1, x2 y2, x3 y3, x4 y4

not:
x1 y1 x2 y2 x3 y3
x1, y1, x2, y2, x3, y3, x4, y4
(x1, y1), (x2, y2), (x3, y3)
or other variations on that theme.

In this post, we’ll look at strategies for backups and disaster recovery.

Note: I am giving a talk on Backups and Disaster Recovery Best Practices on July 27th.

Register Now

When discussing disaster recovery, it’s important to take your business’ continuity plan into consideration. Backup and recovery processes are a critical part of any application infrastructure.

A well-tested backup and recovery system can be the difference between a minor outage and the end of your business.

You will want to take …

MySQL 8 is shaping up quite nicely. And we are having a blast in the MySQL replication team while this is happening. We are continuously improving all-things-replication by introducing new and interesting features. In addition, we have been listening to our community and addressing their feedback.…