Introduction Last week, Burkhard Graves asked me to answer the following StackOverflow question: And, since he wasn’t convinced about my answer: I decided to turn it into a dedicated article and explain how UPSERT and MERGE work in the top 4 most common relational database systems: Oracle, SQL Server, PostgreSQL, and MySQL. Domain Model For … Continue reading How do UPSERT and MERGE work in Oracle, SQL Server, PostgreSQL and MySQL →

The post How do UPSERT and MERGE work in Oracle, SQL Server, PostgreSQL and MySQL appeared first on Vlad Mihalcea's Blog.

Authors: Sunny Bains, Jiamin Huang (University of Michigan)

What is Transaction Scheduling?

Locking is one of the most popular mechanisms for concurrency control in most database systems, including Oracle MySQL. One major question, however, seems to have been overlooked by all database vendors:

Q: When multiple transactions are waiting for a lock on the same object, which one(s) should get the lock first?…

There’s a GTID_SUBTRACT function, and the manual shows how to write your own cheap GTID_UNION, but not a GTID_INTERSECT. Fortunately it’s easy to write your own, as it’s just subtracting twice.

CREATE FUNCTION GTID_INTERSECT(g1 TEXT, g2 TEXT)
RETURNS TEXT DETERMINISTIC
RETURN GTID_SUBTRACT(g1, GTID_SUBTRACT(g1, g2));

What use is it?

SET @slave_executed = '33738f8c-c1a5-11e7-8fc3-0a002700000f:1-681577,
421d139e-04b9-11e7-b702-0050569935dc:1-13764443,
52b9a949-d79d-11e3-80dd-0050568d193e:1-1207378:1207380-1261803:1261805-1267098:1267100-1267416:1267418-1589733';

SET @master_executed = '33738f8c-c1a5-11e7-8fc3-0a002700000f:1-730294,
421d139e-04b9-11e7-b702-0050569935dc:1-13764443,
52b9a949-d79d-11e3-80dd-0050568d193e:1-1207378:1207380-1261803:1261805-1589733';

SET @master_purged = '33738f8c-c1a5-11e7-8fc3-0a002700000f:1-681582,
…

Today I am going to share with you how to create insert update delete operation with validation in codeigniter 3 application with demo examplethis tutorial will help to create simple CRUD Create Read Update Delete Operation application using MySQL Database with validation As we know well we al

Today I am going to share with you how to create insert update delete operation with validation in codeigniter 3 application with demo examplethis tutorial will help to create simple CRUD Create Read Update Delete Operation application using MySQL Database with validation As we know well we al

MySQL Change default directories

While reading this heading everybody things like, yeah its pretty old topic, we can get many articles by googling. But you know what sometimes well known things never work for us. This time it happened for me, my bad. I have done this many times. But most of us changed the default Data Directory only. Only a few of us thinking about change MySQL default data,binlog, error log directories.

I can easily change the Data directory, But while enabling binlog, and error log I got an error.

mysqld: File '/mysql/binlog/mysql-bin.index' not found (Errcode: 13)

So this is the reason for wrote this blog.

My Server Setup:

OS: Ubuntu 14.04LTS 64Bit

MySQL: 5.5.58

Destination Directories:

Data: /mysql/data

Binlog: /mysql/data

…

There are a few MySQL or mixed MySQL/other-DBs jobs in the UK if you are looking to get into the industry or move up:

• Senior/Team Lead MySQL DBA - London Waterloo
• DBA - MySQL - sevenoaks
• MySQL DBA - Up to 55,000 - Surrey
• Senior Cloud Database Engineer - MySQL, Linux, AWS
• …

In the 1990s C.J.Date said: "The rule by which it is determined within the standard that one key word needs to be reserved while another need not be is not clear to this writer."

Nothing has changed since then, except there are more reserved words. No DBMS uses the standard list. So I think that it is probably best to know what words are reserved in product X that are not reserved in product Y. If you know, you can avoid syntax errors when you update or migrate.

I'll present several comparisons, ending with a grand chart of all the reserved words in the standard and six current DBMSs.

First here's a screenshot of ocelotgui where I'm hovering over the word BEGIN.

What I'm illustrating is that you can't depend on intuition and assume BEGIN is reserved, but a GUI client can tell you from context: it's a …

Join Percona Chief Evangelist Colin Charles as he covers happenings, gives pointers and provides musings on the open source database community.

This week we saw the closing of the CFPs for MariaDB’s user conference, M18. Peter Zaitsev and I submitted for Percona (don’t forget that there is also a developer’s conference tacked on to this event). We don’t have high expectations of getting a talk there, but hey – you never know! I submitted a talk on running MariaDB in the cloud (either hosted on Amazon RDS or Rackspace) or in your own compute instance. Another talk on capacity planning seemed to make sense as well. …

Percona announces the release of Percona Monitoring and Management 1.4.1 on Thursday, November 2nd, 2017. This release contains fixes to bugs found after Percona Monitoring and Management 1.4.0 was released. It also introduces two important improvements. We replaced the btrfs file system with XFS in AMI and OVF images, and the Prometheus dashboard has been enhanced to offer more information.

For install and upgrade instructions, see Deploying Percona Monitoring and Management.

Improvements

• PMM-1567: The  …