Seems I have turned into a bit of a news source. dbWatch Software sent me a news release on their dbWatch monitoring platform, which looks like it might be an interesting product for those who work in a heterogeneous database environment. Here’s the release.
InnoDB is a storage engine that uses MVCC (described shortly) to provide ACID-compliant transactional data storage using row-level locking. MVCC stands for Multi-Version Concurrency Control. It is how InnoDB allows multiple transactions to look at a data set of one or more tables and have a consistent view of the data. MVCC keeps a virtual snapshot of the dataset for each transaction. An example will make this clear.
I was contacted by the folks at MONyog and asked if I would review MONyog. Since using MONyog is something I have been wanting to do for a while, I jumped at the chance. Of course, “jumped” is relative; Rohit asked me at the MySQL User Conference back in April, and here it is two months later, in June. My apologies to folks for being slow. Have a look.
I began to write a post on InnoDB transactions, but there was so much background material that I decided first to write a post introducing transactions, and then one on how InnoDB implements them. If there is good response from these two posts, I will continue with other posts on the major storage engines and their transactional characteristics.
A few days back I read the Workbench Team’s blog and was curious about the printing capabilities of MySQL Workbench Community edition. As we already know by now, it only allows you to print a single page. I needed to review a customer query which had several tables and some complicated relationships, so I decided to take Workbench Community for a spin (I already knew the Standard edition from my previous job) and tested the following steps…Here’s where the heavy testing started. Besides the PDF file I also created an SVG and an EPS. All of these are scalable. My thinking was that if I imported these files into the right tools, I should be able to get a bigger printout.
In this blog entry, I will discuss strategies and techniques to resolve ‘log file sync’ waits. This entry is intended to show an approach based upon scientific principles, not necessarily a step-by-step guide. Let’s understand how LGWR is inherent in implementing the commit mechanism first.
This is what I found in the APEX documentation that comes with Oracle 11g, in the chapter describing building a very simple application…Making sure the database instance couldn’t potentially use an index in DEPARTMENT_ID column? Why on earth would you teach novice APEX developers such a horrible practice? To me, it’s one more confirmation that Oracle can do an excellent RDBMS, but when it comes to database applications development . . .
Welcome to the 103rd edition of Log Buffer, the weekly review of database blogs.
As an editor, I cringe at the title of this post. However, it is absolutely accurate. Recently, we had a situation where we had two servers running Sun Solaris 10 on some high-end Sun hardware. The two servers are configured in a master-master circular replication setup. Here is the problem. On both servers, the error logs were being created incorrectly. On one of them, it was creating an error log that was 154 megabytes in size.Â FLUSH LOGS worked, but the newly-created error log would be the same size. While there was some data in the file that I could use the cat, head or string command to discern, the majority of the file was not text data. If anyone has any thoughts or a similar experience, I would love to hear from you!
Small local user group meetings have their own beauty because of the special intimate atmosphere. We expected somewhat higher attendance but it seems that people were already in the holiday mode. The presentation itself went very well and I liked my pace since I didn’t have any time pressure. I’ve done this presentation before in 45 minutes and this time it took slightly more than an hour but I was able to spend additional time on few more complex topics and explain the underlying concepts making sure we all are on the same page. I also enjoyed the questions during the presentation — always a pleasure to know which parts are more interesting to the audience and questions is one of the best indicators. Another one is when people take notes. All in all — it was a very encouraging hour. Thanks to every one who attended!