Since the release of the 5.6 Community MySQL Server there is support for the milliseconds value in Time, TimeStamp and DateTime types.  You can find more information on this new feature at (http://dev.mysql.com/doc/refman/5.6/en/fractional-seconds.html).  Starting with version 6.5, Connector/Net fully supports milliseconds. This support does not affect compatibility with older versions of MySQL and it gives you the ability to use fractional seconds when combining Connector/Net 6.5 with MySQL Server 5.6 or later.  Let's see how we should use it.

Creating a DateTime column that include Milliseconds value.

You can do this either using Connector/Net or using any MySQL client with a valid connection to your database.

For this case we're going to use MySqlCommand class within a console application in VS 2010.

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Galera replication 2.0 beta has been released, get your download in https://launchpad.net/galera/2.x/22.2.0beta

This release comes only with Galera library build, there are 64bit DEB and RPM packages available for download. To test Galera 2.0 replication, install the beta library in Galera cluster 1.1 and you are ready to go (wsrep API version #22 is required).

Galera 2.0 has as a new feature incremental state transfer (IST). Earlier Galera cluster behavior was to always copy full database to new joining node. With IST, the previous state of joining node is taken in consideration, and only the delta of missing transactions will be transferred and applied in joining node. Applications having big database, will experience a great performance boost with node join operations.

The beta cycle is expected to continue for a few weeks and is then followed by …

I guess I’m first to post in 2012 so Happy New Year all blog readers !
Now back to HardCore MySQL business – foreign Keys. MySQL supported Foreign Keys for Innodb for many years, yet rudimentary support initially added in MySQL 3.23.44 have not been improved in new releases as much as I’d like. We still get cryptic error messages such as “ERROR 1025 (HY000): Error on rename of ‘./test/child’ to ‘./test/#sql2-496-40a5′ (errno: 152)” in many cases and foreign keys are still handled on storage engine level making them not working for partitioned tables as well as making foreign keys performed row by row which often can be very inefficient.
As results of Foreign Key limitations you might need to get rid of them, yet this leaves you up for a final bite – dropping foreign keys requires table rebuild. Yes you get it right even though Innodb is able to drop indexes without rebuilding table since MySQL 5.1 (Innodb Plugin) …

My title page contents closely resembling the original concerning its shape and appearance". Did you notice something in the definition? See the replica is actually a "close resemblance" and not an mirror image. When it comes to MySQL replication the above definition of the replica is very true - your replicated slaves will "closely resemble" your master database and will not be an exact copy.

MySQL replication is very widely used for MySQL HA (High Availability) and the general presumption and expectation is that the master/master (or master/slave) produce exact copy of the master. False expectation to say the least, well to the defense of MySQL replication I might say that it was never designed for HA, it was merely adapted  to be used for MySQL high availability. To be fair this is true not only MySQL replication but for any other asynchronous replication out there. The database replication was designed for "data …

Fresh on the codecentric blog is my new post about using SOAP web services from an iOS client application.

It features a short comparison of the current state of frameworks and tools with the Java world, and then focusses on the sudzc open source library that takes a very interesting approach in generating web service client artifacts by transforming the service's WSDL into Objective-C classes using XSL transformations.

The post is available in German as well.

Read the original article at How about an easier tip jar?

Walking around New York you find yourself stopping at plenty of different places to grab some takeout for lunch. There are Vietnamese sandwich places, pizza shops, noodle bars, taco stands, juice bars and of course your daily coffee shop. You'll find an endless variety.

As is customary in New York, even for takeout there is usually a tip jar at the checkout. Many of them have a large bowl, or glass jar in which you can throw your change as tips, or if you really love the place and service, a couple of dollars.

Of late I've noticed a few have placed those small plastic boxes with a tiny slot on the top. You try to put some change in the slot, and half of the money falls on the floor. It's as frustrating as threading a needle while suffering from astigmatic vision. Now when I …

Read the original article at Review: Here Comes Everybody by Clay Shirky

Clay Shirky tells a great story. Here Comes Everybody begins with a case of a lost phone in a taxi cab, and the extraordinary turn of events that led to the owner retrieving it. From photos posted online, to NYPD who were uninterested in following up, to taking it all online. Through that online publicity, the story got picked up by the NY Times and CNN, which put pressure on the police to track down the taxi.  It's a great example that illustrates the nuances, both good and bad, powerful and persistent that the Internet can unleash.

Throughout the book he weaves stories about the network effect, friends and friends of friends, and how that impacts information, organization, and the spread …

Can an execution of 3-way join use only indexes and not touch table rows at all? If we have MyISAM tables it's just impossible. Yet with InnoDB tables it would be possible if we could exploit so called extended keys – the regular secondary keys extended by the components of the primary key. The fact is the InnoDB engine works fine if you pass a key extended by primary key components, and, it uses the key to the full length without trimming it up to the base key fields. In the result we have a more narrow search and numerous obvious benefits from it.

Let's see how extended keys could be employed by execution for the following query built over a DBT-3/TPC-H database with one added index defined on p_retailprice.

select o_orderkey
 from part, lineitem, orders
 where p_retailprice > 2095 and o_orderdate='1992-07-01'
       and …

In my previous posting I explained how to reset MySQL root password using" --init-file"  MySQL start up parameter. Yet there is another option using "--skip-grant-tables" MySQL parameter.

Here is how to do it:

1. Shutdown MySQL using /etc/init.d/mysqld stop


2. Star MySQL using "--skip-grant-tables" parameter

/etc/init.d/mysqld-safe --skip-grant-tables


MySQL is now running in back round since we used (&) option 
3. Now we can reset any password since MySQL is not validating permissions:
Login as root …