In writing a recommendation for our Web development team on how to use MySQL, I came up with the following list, which I want to share: What kind of queries are bad for MySQL?

• Any query is bad. Send a query only if you must. (Hint: use caching like memcache or redis)
• Queries that examine many rows are bad. Try instead to use…
  

      SELECT col1 FROM table1 WHERE primary_key_column=SOMETHING

  
  . Or at least
  

  secondary_key_column=SOMETHING

  
  . If it is still not possible, try to make the query examine the least amount of rows possible (zero is ideal, as we come to the first case here)
• Queries with JOINS are bad. Try to denormalize the table to avoid JOINS. Example: original query
  

      SELECT t2.value FROM t2 JOIN t1 ON (t1.id=t2.tid) WHERE t1.orderdate=NOW()

  
  . This can be denormalized by copying the column orderdate from table …

In my previous post, Creating a basic C/C++ Program to Interact with MySQL and MariaDB, I ran into some errors along the way, so I wanted to share those and their resolutions.

1. fatal error C1083: Cannot open include file: ‘mysql.h’: No such file or directory

mysql1.c
mysql1.c(2) : fatal error C1083: Cannot open include file: 'mysql.h':
No such file or directory

At this point, my cl command was:

cl /I "C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\include"
mysql1.c

So I needed to include the directory that contained mysql.h as well. So the above changed to:

cl /I "C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\include"
/I "C:\Program Files\MySQL\MySQL Server 5.5\include" mysql1.c

2. error C2061: syntax error : identifier ‘SOCKET’

This was actually a small slew of simple syntax errors. I …

In this post, I’ll cover how to create a simple C/C++ program that interacts with MySQL using the C API (and Connector/C). I discussed in a previous post how to install the C Connector (both SkySQL and MySQL’s), so please refer to that if you are looking for more specifics on that.

So once you have that set up, then there are just a few more things you need to have in order – at least this was the case in my environment.

1. Create a program (this one simply connects to the server and retrieves the server version):

#include <stdio.h>
#include <windows.h>
#include <mysql.h>

MYSQL *conn;
int version = 1;

int main ( int argc, char *argv[] )
{
    conn = mysql_init ( NULL );
    mysql_real_connect ( conn, "localhost", "root",
            "password", "test", 3308, NULL, 0 );
        version = mysql_get_server_version( conn ); …

I’m writing a post on how to create your first C/C++ program for MySQL (using Windows, and from the command line). A prerequisite for that is to have a C Connector, such as MySQL Connector/C or SkySQL C Connector, so the program can communicate with mysqld.

I didn’t want that post to be too scattered, so I decided to split it into two, more focused posts. That said, this first post will focus on the Connector, and the next post will actually cover the program itself.

Installing and using Connector/C with MySQL is quite simple, so I wanted to show how easy it is. I also wanted to show examples with both SkySQL C Connector with MariaDB (which also works with MySQL) and Connector/C with MySQL, since both are widely used. I also wanted to show some common errors one might encounter and their resolutions, so hopefully this will help anyone who might have issues …

Multi master topologies blues

Tungsten Replicator is a powerful replication engine that, in addition to providing the same features as MySQL Replication, can also create several topologies, such as

• all-masters: every master in the deployment is a master, and all nodes are connected point-to-point, so that there is no single point of failure (SPOF).
• fan-in: Several masters can replicate into a single slave;
• star: It’s an all-masters topology, where one node acts as hub which simplifies the deployment at the price of creating a SPOF.

The real weakness of these topologies is that they don’t come together easily. Installation requires several commands, and running them unassisted is a daunting task. Some time ago, we introduced a set of scripts (the Tungsten Cookbook) that allow you to install multi-master topologies with a …

Percona is glad to announce the release of Percona Toolkit 2.1.10 on July 18th, 2013 (Downloads are available here).

Bugs Fixed:

• Unfortunately, the relatively new --utc option for pt-heart was still broken because “MySQL interprets date as a value in the current time zone and converts it to an internal value in UTC.” Now the tool works correctly with --utc by specifying “SET time_zone='+0:00'“, and older versions of the tool can be made to work by specifying --set-vars "time_zone='+0:00'". Bug fixed …

MySQL Community BOF at OSCON

Moderated by: Dave Stokes
7:00pm Wednesday, 07/24/2013
Location: D136

There will be a Birds Of a Feather seesion for all interested in MySQL, the MySQL Community, and all the surrounding technology that relies on MySQL. Lets talk about the current and future of MySQL — where you think it should be heading — and network with others. All levels of audience experience are welcome.

The MariaDB project is pleased to announce the immediate availability of MariaDB 5.5.32. This is a Stable (GA) release. See the Release Notes and Changelog for detailed information on this release and the What is MariaDB 5.5? page in the AskMonty Knowledgebase for general information about the MariaDB 5.5 series.

Download MariaDB 5.5.32

Release Notes Changelog …

Thu, 2013-07-18 16:22dbart

The MariaDB project is pleased to announce the immediate availability of MariaDB 5.5.32. This is a Stable (GA) release. See the Release Notes and Changelog for detailed information on this release and the What is MariaDB 5.5? page in the AskMonty Knowledgebase for general information about the MariaDB 5.5 series.

Download MariaDB 5.5.32

Release Notes …