SQL Relay 0.57 is now available!
Windows Support
Support for Windows is much improved in this release. The command line clients all work now - sqlrsh, sqlr-export, sqlr-import, etc. The C/C++, C# and ADO.NET API's have worked for a while, but are now joined by native API's for Perl, Python, PHP and Java as well as drivers for Perl DBI, Python DB and PHP PDO.
It is possible to build all of this on Windows using MS Visual Studio or MS Visual Studio Express but it is currently quite difficult and requires specific versions of things to be installed in the right places. PHP is especially difficult to work with. In fact, I'm honestly not sure how 3rd party developers are expected to develop drivers for Windows. I had to shoehorn the headers in manually from the source code.
However... The SQL Relay Binary Distribution for Windows is now available (for a few bucks) and provides installers for binary versions of the above-mentioned software.
So... in addition to just accessing SQL Relay from command line clients, SQL Relay applications, including web-based applications, can now be developed for Windows in C, C++, C# (and other .NET languages), Perl, Python, PHP and Java.
Give it a try, let me know if you run into trouble.
Oracle "describe table" Improvements
In sqlrsh if you run "describe tablename" it returns info about the columns of the table - name, type, size, etc. This is accomplished by a call to the getColumnList() method of the C++ API. All SQL Relay API's support this method, and it has been improved.
For oracle tables, if a column is a primary, unique or foreign key, that information is now given. In previous releases it was not. This is a fairly expensive operation, as it turns out, so there is a config parameter to disable looking up keys. See disablekeylookup=yes/no in the oracle connection string in the SQL Relay Configuration Reference for more info.
Also, if you run "describe" on a synonym to a table in another schema, it will now return information about that table. In previous releases, only tables could be described.
Rudiments Improvements
The Rudiments library that SQL Relay depends on has been updated to randomize the list of hosts returned by DNS server when using round-robin DNS. If you are using round robin DNS to distribute SQL Relay clients over a pool of SQL Relay servers, then the behavior may different than in previous releases. In particular, if one host is down, then rather than slamming the next host in the list with all of the downed host's traffic, load will be distributed over the remaining hosts. This feature was added to work around an issue with many recent-ish implementations of getaddrinfo().
Rudiments has also been updated to support kqueue, epoll, port_create, /dev/poll, poll and select in its listener class. There should be no concerns now about large numbers of clients queuing up on the listener, or with listener performance with regard to using select internally.
See the rudiments release announcement for more information on these updates.
Bug Fixes and Minor Improvements
This release features a few bug fixes and minor improvements too.
The Python API's getRowDictionary method had a bug where None's were being returned as 0's when getNullsAsNones was set. That's fixed now.
Sensible errors are now returned when the format of a numeric bind variable is incorrect when using mysql, firebird or oracle. An error was fixed that could cause mysql connection to loop up if alphanumeric bind variable names were used instead of numbers. A bind-variable translation bug was fixed that could cause variables not to be translated when multiple formats are used in the same query and one of them is the correct format too.
The --with-system-libtool configure option was broken but it's fixed now.
Minix 3.3.0 is now supported. At least the client side is. Ie. you can access Oracle from Minix 3.3.0 using sqlrsh and SQL Relay running on another system. The server-side stuff doens't work yet. The Minix kernel doesn't support semaphores by default and Minix 3.3.0 ships without kernel source. I'm not sure if it supports semaphores at all though, so maybe that's moot.
The drop-in replacement library for MySQL had bugs with its implementations of mysql_row_seek() and mysql_row_tell(). Those are fixed now.
The configure script properly detects Maria DB on Ubuntu 14.04.1 now.
Give it a try and report any bugs that you find!
