Changes (as compared to 4.50.339) include:
Bug fixes:
* The error on entering selection criteria after selecting Group By fields in Query Builder fixed (T26884)
* The problem with showing 0 as a parameter value instead of NULL in the parameter editor fixed (T26867)
* Removing field’s autoincrement sign on adding index in the table fixed (T24859)
* Extra new line on copying data from a cell in Data Editor removed (T27021)
* The problem with losing ON UPDATE CURRENT_TIMESTAMP during editing a table fixed (T27090)
* The problems with connecting to MySQL Server via SSH tunnel fixed (T26911, T20079)
* InvalidOperationExceptions on generating schema synchronization script in the Schema Comparison tool fixed (T27106, T27108)

Downloads: http://www.devart.com/dbforge/mysql/studio/download.html

Changes (as compared to 4.50.339) include:
Bug fixes:
* The error on entering selection criteria after selecting Group By fields in Query Builder fixed (T26884)
* The problem with showing 0 as a parameter value instead of NULL in the parameter editor fixed (T26867)
* Removing field’s autoincrement sign on adding index in the table fixed (T24859)
* Extra new line on copying data from a cell in Data Editor removed (T27021)
* The problem with losing ON UPDATE CURRENT_TIMESTAMP during editing a table fixed (T27090)
* The problems with connecting to MySQL Server via SSH tunnel fixed (T26911, T20079)
* InvalidOperationExceptions on generating schema synchronization script in the Schema Comparison tool fixed (T27106, T27108)

Downloads: http://www.devart.com/dbforge/mysql/studio/download.html

Alex Popescu wrote a blog post asking some questions about RethinkDB and SSD performance. There is a related Twitter conversation happening here. There are two fundamental questions:

• In which cases does SSD performance begin to degrade over time?
• How does the TRIM command affect performance degradation?

The questions are very deep and I cannot do them justice in a single blog post, but I decided to post a quick write-up as a start.

Flash basics

Flash memory has physical properties that prevent overwriting a data block directly. Before new version of the data can be written, a special ERASE command must be called on the block. Erasing a block is significantly slower than writing to a block that has …

The MySQL developer tools team announces the next release of it’s flagship product, MySQL Workbench – version 5.2.33. This is a maintenance release only which corrects some problems we didn’t cover in last release. It contains fixes for 7 bugs or enhancement requests.

As always, we want to thank everyone for the great feedback we have received. This helps us to continuously improve the functionality and stability of MySQL Workbench – we appreciate all your ideas for improving MySQL Workbench.  Please keep sending us your ideas!

MySQL Workbench 5.2 GA

• Data Modeling
• Query (replaces the old MySQL Query Browser)
• Administration (replaces the old MySQL Administrator)

Please get your copy from our Download site. Sources and binary packages are available for several platforms, including Windows, Mac OS X and Linux.

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We’re proud to announce the next release of MySQL Workbench, version 5.2.32. This is a maintenance release featuring
a new and improved UI appearance and several corrections and other enhancements.

The tabbed interface has been refreshed to obtain a clearer separation between different modules of Workbench, while improving responsiveness when switching between tabs. The Query Formatter has been rewritten and is now faster and more robust on its handling of queries. The layout of the Administration module has been changed to allow for easier future expansion and use less vertical screen space. Parts that had problems managing MySQL 5.5 servers have been fixed along other total of 53 bugs or enhancement requests have been addressed.

As always, we want to thank everyone for the great feedback we have received. This helps us to continuously improve the functionality and stability of MySQL Workbench – we appreciate all your …

A few days ago Salvatore Sanfilippo wrote about his work on a new Redis diskstore – a reworking of the old VM layer based on a different set of assumptions and tradeoffs. I was very interested in the new approach because it is very similar to the RethinkDB caching architecture in principle. When we designed our caching layer we had a number of constraints we needed to satisfy:

• Performance – the system needed to work at memory speeds when the data fits into RAM, as well as when the data far exceeds the amount of available RAM, but the active working dataset mostly fits into RAM. Once the active dataset no longer fits into RAM, the system still needs to work at the speed of the underlying storage layer.
…

On my computer, the callstack of a new process is around 10MB*. Modern operating system automatically reserve some amount of virtual memory and install protections on the page below the stack to create a segmentation fault on stack overflow. This ensures that a stack overflow won’t go corrupting random parts of memory.

We want to have a lot of coroutines, so they should have smaller stacks, maybe 16 or 64KB. This makes stack overflow an even greater possibility, but at the same time, coroutines implemented in user space don’t get this checking for free—we have to build it ourselves. In the process, we can even do better: we can give some information about the coroutine which crashed. Here’s the idea:

• Memory-protect the page on the bottom of the stack (remember, x86 callstacks grow down) to disallow reads and writes.
• Install a signal handler for SIGSEGV.
• In the handler, examine which address …

Previously, I wrote about using coroutines in RethinkDB. Coroutines are a nice alternative to callbacks because they are easier to program in, and they are a nice alternative to threads because of their greater performance. But how fast are they?

Just using an off-the-shelf library like libcoroutine isn’t as fast as you might think. The graph below shows the huge performance degradation of a naive implementation of coroutines (the short red bar) compared to the old callback-based code (the blue bar on the left). But with the right set of optimizations, we can recover a level of performance about equal to the non-coroutine version. With these optimizations, throughput is recorded as the pink bar on the right, which is within the margin of error of the original version.

The improvement comes from  two …

We’re proud to announce the next release of MySQL Workbench, version 5.2.31. This is a maintenance release focusing on general product improvement and usability.

We managed to close 97 bugs for this release.

MySQL Workbench:  Remote Administration on Windows – Support for Windows “Remote” Management within the New Server Instance Wizard and Manage Server Instance Form. This works for servers on the same domain (or trusted) – ie typical Windows LAN environments.  We expect Windows users to prefer this “native” way to do remote admin on Windows.  SSH remote admin has been available for some time on Windows, Mac OS, and Linux.

MySQL Workbench:  Utilities Plugin – Starts a shell that contains a set of python scripts that perform basic tasks such as copying, exporting, and importing databases, finding database objects or processes, cloning servers and cloning users.

MySQL Workbench: …

We’re proud to announce the next release of MySQL Workbench, version 5.2.30. This is a maintenance release focusing on general product improvement and usability. In addition to that, we have added a small set of Text-Formatting-Plugins to the SQL Editor to help format/structure your SQL Queries.

As always, we want to thank everyone for the great feedback we have received. This helps us to continuously improve the functionality and stability of MySQL Workbench – we appreciate all your ideas for improving MySQL Workbench.  Please keep sending us your ideas!

About the Query-Formatter

In the Edit->Format menu of Workbench’s SQL Editor you will see a set of functions that assist in reformatting your SQL Queries, for example “Beautify Query”, “UPCASE Keywords”, etc.

MySQL Workbench 5.2 GA

• Data Modeling
• Query (replaces the old MySQL Query Browser)
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