Web Design Tips and Tricks

Does Your Website Induce Seizures?

Get Web Design Tips and Tricks on mps-web-design.com. Does Your Website Induce Seizures? topic will increase your understanding on Web Design Tips and Tricks. We at mps-web-design.com only provide news, articles, information in Web Design Tips and Tricks. Web Design Tips and Tricks at mps-web-design.com provides the most up to date news and articles. If you have questions please do not hesitate to contact us.

QUESTION:
We promote our web site in all our ad campaigns, but according to my website statistics program, we are getting very few visitors who click past the first page. The site has a cool Flash introduction page that the designer said would impress visitors, but it doesn’t seem to be working. What can we do to get people to spend more time on the site? -- Christopher O.

ANSWER:
The first thing you should do, Christopher, is find that designer and beat the living Flash out of him. It won’t increase the time visitors spend on your website, but it will make you feel better after you’ve read this column.

What your designer thought would appeal to visitors is probably the very thing that is driving them away. A Flash introduction page (Macromedia Flash is a software program used to create animations for Web pages) may seem “cool” to you, but from a website visitor’s point of view, they can be about as appealing as sitting in the front row of a Pokemon movie with four hundred screaming six year olds (and here comes the segue, folks).

In December, 1997, during an episode of Pokemon, the popular Japanese TV cartoon that has spawned everything from movies to action figures to lunch boxes, a scene featured a rocket explosion that flashed red and blue lights in rapid succession.

After the episode, over 600 children were taken to hospitals complaining of seizures, blurred vision, headaches, dizziness, and nausea. Any adult who has ever been exposed to Pokemon for more than two seconds can understand the nausea, but the seizures at first baffled doctors.

Scientists ultimately came to attribute the mass reaction to “photosensitive seizures,” which are brought on by exposure to certain visual stimuli like rapidly flashing lights on a TV screen.

Remember when your mom told you not to sit so close to the TV or you’d ruin your eyes? Turns out she knew what she was talking about. Who knew?

The event caused such concern that Japanese broadcasters and health officials met to discuss ways to prevent future occurrences of bad-cartoon induced illnesses. They established guidelines for the broadcast of flashing images: no image may flicker faster than three times per second; flashing images should be displayed for no more than two seconds; and stripes, whorls, and concentric circles should not take up the largest portion of a TV screen.

It’s my humble opinion that these rules should apply to websites as well. I’ve been in the Internet design business for nearly a decade and I have been witness to numerous websites that could induce photosensitive seizures in blind moles. It sounds like your website might be suffering from a similar ailment.

If visitor’s are not clicking past your fancy Flash intro page, you don’t have to be a genius to figure out that therein lies your problem. Remove the Flash intro page for a few weeks to see if your website’s click-through rate improves and the number of page views increase. “Click-through rate” refers to the number of visitors who click links on your homepage to go deeper into your site. “Page views” refers to the overall number of web pages that were viewed by visitors. If click-through and page view rates improve, you’ll know that the Flash intro was your problem.

Here are a few other things you can do to make sure your site offers visitors a pleasant – and seizure free - browsing experience.

Sit In The Visitor’s Chair

The best way to make sure your website is as user friendly as it can be, is to sit down at a computer and approach your site from a typical visitor's point of view. Try to imagine that you are seeing the site for the first time. If you are unable to do this, have a friend who has never seen the site click around and offer comments while you take notes.

Have your friend assess the following points: Is the site appealing to the eye? Are the colors pleasing and complimentary? Is the site easy to navigate? Are the topical categories and subcategories in logical order? Is it easy to find what you're looking for? Does the site have a search engine to make finding things easier? Is every feature of the site less than two or three clicks away? If the answer to any or all of these points is no, you have some work to do.

Don’t Dictate Technology

One sure fire way to repel web site visitors is to require that they have special browser plug-ins or 3rd party add-on browser software installed to view your site. Dictating that the user download and install software is not your place and users will resent you (and your business) for it. Visiting your site should be an effortless pleasure, not a technological chore.

Don’t Make Them Wait

If your homepage takes longer than 20 seconds to download (appear in the visitor’s browser) you are losing visitors, period. Gratuitous animation, large graphics, poorly formatted HTML, bad page layout, and a number of other factors can increase download time. You might have the greatest web site in the world, but if it takes ten minutes to download no one will ever see it.

The lessons to be learned, then, are threefold. One: a website should be designed to satisfy the visitor’s needs, not to pacify the site designer’s ego.

Two: visitors to a business website are not there to be awed and entertained. They are there looking for information, and unless you give it to them quickly and effortlessly, they will go elsewhere to get it.

And Three: for better mental and physical health avoid Pokemon at all costs.

Some simple suggestions

Well I don't consider myself an expert, I do have experience with working with larger datasets and there are a couple of things that I always do to keep queries performing well.

Optimize Queries with EXPLAIN

Explain is your friend, get to know it well. If you take the time to read thru the Explain documentation on the MySQL site, you will find some valuable information, some of which is hilighted below.

Optimizing joins

Single sweep what?

MySQL resolves all joins using a single-sweep multi-join method. This means that MySQL reads a row from the first table, and then finds a matching row in the second table, the third table, and so on. When all tables are processed, MySQL outputs the selected columns and backtracks through the table list until a table is found for which there are more matching rows. The next row is read from this table and the process continues with the next table.

Why is this important? Imagine a main table - tableA - with 80,000 rows of data. This table has a corresponding n:n table that maps entries in tableA with a locations table. A query could be written as:

SELECT tableA.*, locations.location from tableA 
Left Join tableA2locations on 
tableA2locations.tableA_id = tableA.id
Left Join locations on 
tableA2locations.location_id = locations.id
where locations.location = 'sometown'

Keeping the above quote in mind, MySQL will read a row from the first table and join the corresponding data from the joined tables for that row and then sweep thru the rest of the data, joining as it goes along.

This leads us into the following section.

Number of rows needed to execute a query

You can get a good indication of how good a join is by taking the product of the values in the rows column of the EXPLAIN output. This should tell you roughly how many rows MySQL must examine to execute the query.

From the above, you can determine that for a query on tables that have not been properly indexed, a join can quickly become unwieldy when dealing simply with three tables with records in the thousands (1000*1000*1000 = a slow query). See HackMySQL for a good example of this.

Reducing the number of rows needed to execute a query

So beyond indexing properly for joins, you can still end up with a query that runs in a way that causes a bottleneck.

Taking our example from above, imagine that we use a where clause that limits the tableA selection to half (tableA.foo = 'bar' below):

SELECT tableA.*, locations.location from tableA 
Left Join tableA2locations on 
tableA2locations.tableA_id = tableA.id
Left Join locations on 
tableA2locations.location_id = locations.id
where locations.location = 'sometown' and tableA.foo = 'bar'

This starts us out with 40,000 rows of tableA data to examine. If there are a further 2000 rows from tableA2locations, thats 800,000 rows of data. Not astronomical, but significant. If this was a 3 or 4 table join, things could get ugly. What to do? The answer may be obvious to some: select first with the most limiting table:

SELECT tableA.*, locations.location from locations 
Left Join tableA2locations on 
tableA2locations.location_id = locations.id
Left Join tableA on 
tableA2locations.tableA_id = tableA.id
where locations.location = 'sometown' and tableA.foo = 'bar'

This starts us out with 1 selection from the locations table, then 2000 from tableA2locations. If the join between tableA2locations and tableA is indexed correctly, we are then left with an index join based on ID, rather then having to initially select 40,000 rows from tableA as in the previous example.

When I first started programming, it made sense to me to select from the main table (tableA) and join the lookups. But once you add some data to the mix and start to play with Explain, you quickly realize that selecting from the limiting table can make your server's life a little easier.

For further reading on the topic, I always send people to HackMySQL when they ask, so for more tips and tricks, be sure to have a read thru the optimize section of that site.

More Articles: