Full Outer Join

During mid-September, WowStead changed its hosting partner to Curse Inc.. In doing so, it needed to migrate vast amounts of data over to the new Web servers and, among other things, merge the databases of both websites together. This was necessary given that users will log in to WowStead using their Curse Account. Unfortunately, several problems arose from the process:

• WowStead users that do not have a Curse Account cannot log in to WowStead.
• WowStead users that do not have a Curse Account have lost access to their characters and subsequently need to reclaim them.
• In the vice versa of the above, users have access to their characters but do not own the account they were assigned.

While explanations of what went wrong are not readily forthcoming, a likely cause is the misuse of the methods adopted to merge the two databases together. Given the popularity of relational databases in storing website data, one can contemplate how the use of relational algebra can bring about such complications.

Ulduar Constellations [Windows 7 theme]

Ulduar may well be one of the most awe-inspiring and (quite literally) captivating places in Azeroth. This theme brings a few of its highlights (in particular, its many constellation-like sculptures) to your Windows 7 desktop.

As I do not have file hosting available to me for hosting the .themepack file, I will give instructions apply it manually. This theme offers the following appearance customisations:

• Desktop background
• Window colour
• Sounds
• Screensaver

WoW Mathematics: Steady-State Health Level

In the final phase of the Anub'arak encounter in the Trial of the Crusader (ToC), healers must heal through a variety of sources of damage, including Penetrating Cold and Leeching Swarm. While the former deals constant damage over time, the latter does more damage the higher players' health levels are! The raid might be interested in knowing the optimal health level the healer(s) can keep the players at.

At the steady-state health level, DPS of Anub'arak against the raid equals the HPS of the healers for the raid. From here, health levels do not tend to move either way; they are stable, and this determines whether the healers can provide enough healing.

Summary:

• Where h is the total HPS, r is the proportion of current health Leeching Swarm does as damage, p is the proportion of players affected by Penetrating Cold at cast and P is the tick size of Penetrating Cold, the steady-state health level H* is H* = ¹/_r(h - ³/₁₀pP). It is a good idea to incorporate a buffer against the randomness of the damage.
• For Heroic 10-man, the steady-state health level is H* = 5h - 450, and for Normal 25-man, it is H* ~ 10h - 228.
• As long as the steady-state health level is more than zero, the healing the healers provide is sufficient.

Random Ramblings to 28 August 2010

Carriage return
A typed character that commands the computer to move the cursor to the beginning of the line in a word processor. It is created using the Enter/Return key, which also sends another character that commands the computer to move the cursor to a new line. It is named after the lever on a typewriter, which performs both functions on a typewritten document.

Volumes of Tori and Pyramids

The volume of some solids can be found intuitively (e.g. for a right rectangular prism, V = lbh). However, some more exotic solids will require calculus for their volumes to be found.

Two such solids are the torus (donut) and rectangular pyramid. The former's volume can be found, possibly among others, using the technique of volume by rotation, and the latter's with volume by cross-section. These techniques will be used for deriving the formulae for the volumes of the respective solids. In summary:

• Volume of torus = 2cπ²r²
• Volume of rectangular pyramid = ¹/₃abh

The Stuff of Sensations

With the senses of sight and hearing, a person can see colour and hear sound, respectively. So many hues and timbres exist, yet both are composed of basic elements and can be constructed by combining them in special ways.

Colour

• Sensing body part: Eyes. The lens and cornea focus light to fall on a surface of rods and cones, the pattern of which is sent to the brain as electrical impulses.
• Element: Primary colour
• Medium: Colourants (usually ink) on a white surface, or light on a black surface
• Types of element: For colourants, cyan (reflected blue and green light), magenta (reflected red and blue light) and yellow (reflected green and red light) (practical implementations also use black), although the fine arts has traditionally used blue, red and yellow (which alone cannot theoretically produce black). For light, red (long-wavelength visible light), green (mid-wavelength visible light) and blue (short-wavelength visible light).

Halian Geometry

The Halion encounter in the Ruby Sanctum requires careful positioning and movement in order to conquer it. Certain principles of geometry can help greatly with this endeavour, so it helps to be acquainted with them! Even if they will not be used in actually formulating strategies (since strategies will conveniently be recommended here), it is good to see how they were derived.

Circles and their radii
A circle is a (plane) shape where all points on its perimeter (the circumference) are the same distance from a single point (the centre). A radius is any straight line drawn from the centre to the circumference. Because of the definition of a circle, all radii are of the same length.