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#8885 One Mod Rewrite Rule Won'T Work

Posted by HartleySan on 28 July 2012 - 10:59 AM

If "hiv" is never followed by an e, you could change the one regex as follows:
^hiv[^e]|aids[a-z_\-\./]*$
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#6644 Just Started This Book Today!

Posted by rob on 26 March 2012 - 10:53 AM

It does affect something it affects the source code layout, which is the whole point of using it, to make source code more readable.
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#3208 Some Tips When It Comes To Mysql Queries

Posted by Antonio Conte on 20 August 2011 - 11:19 PM

1. Always name your tables the same way:
There are best practice rules for naming tables. They should always be lowercase, split by underscore ( _ ) and named in plural. If you need to build tables for several purposes, (forums, shops, fruits) prefix them so the appear next to each other.

Examples:
forums_users
forums_posts
shops_products
shops_prices
shops_availability

2. Use normalization rules(!!!) when creating a structure for tables
Larry explains the different forms of normalization very good in this book. Read it thoroughly, UNDERSTAND it, and plan your tables well. The rules are really not that hard to understand, and will allow you to cross-reference tables in an easy way later on. It will make you understand how the data you are using are working. It will make your systems a lot easier to build on and to introduce new features. I promise you, THIS is how you become a wizard when it comes to working with data in several tables.

3. Use white space(!) and use UPPERCASE for mysql functions (See tip #4!)
When your queries becomes increasingly more complex, you should really follow these tips. To demonstrate, I will give you two versions of the exact same code:

CREATE VIEW view_goals_per_game AS

SELECT league.season AS season,
league.id AS league_id,
league.name AS league_name,
goals.match_id AS match_id,
clubs1.name AS hometeam,
clubs2.name AS awayteam,
players.id AS player_id,
CONCAT( players.fornavn, ' ', players.etternavn ) AS player_name,
goals.goal_time AS goal_time,
games.kickoff_time AS kickoff_time

FROM abc_players_goals AS goals

INNER JOIN cnk_soccer_games AS games ON ( goals.match_id = games.id )
INNER JOIN cnk_soccer_clubs AS clubs1 ON ( games.club1_id = clubs1.id )
INNER JOIN cnk_soccer_clubs AS clubs2 ON ( games.club2_id = clubs2.id )
INNER JOIN abc_players AS players ON ( goals.player_id = players.id )
INNER JOIN cnk_soccer_league AS league ON ( league.id = games.league_id )

LIMIT 0, 1000

create view view_goals_per_game as select league.season as season, league.id as league_id, league.name as league_name, goals.match_id as match_id, clubs1.name as hometeam, clubs2.name as awayteam, players.id as player_id, concat( players.fornavn, ' ', players.etternavn ) as player_name, goals.goal_time, games.kickoff_time from abc_players_goals as goals inner join cnk_soccer_games as games on ( goals.match_id = games.id ) inner join cnk_soccer_clubs as clubs1 on ( games.club1_id = clubs1.id ) inner join cnk_soccer_clubs as clubs2 on ( games.club2_id = clubs2.id ) inner join abc_players as players on ( goals.player_id = players.id ) inner join cnk_soccer_league as league on ( league.id = games.league_id ) limit 0 , 1000

Whick one would you like to maintain? :blink:

4: Save your queries in a text editor

Yes! It sound idiotic, right? It's not. Think of this happening: You accidentally delete, modify or overwrite a query you've used a lot of time on. It will save you a lot of time, tears and the life of a few keyboards! This is also leading up tip number 5.

5. Use views instead of customizing your dataset in PHP(!)
This is a real life-saver. Think of it as including ONE central PHP file instead on chancing 10 documents every time you make a change. The views should be written to display AS MUCH information as possible. Try to think of every scenario you may want to use the data. Views are, with a few exceptions, for displaying data; hence it's name.

NOTE: After the creation of a view, you CANNOT modify it. This is why you should follow step 4.

- Views are really easy to create:
[u][i]CREATE VIEW the_name_of_the_view AS[/i][/u]
SELECT *
FROM table1

The query used in tip #3 is a view. It would allow you to sort by a specific league, match_id, player_id or by kickoff_time. The view is used to display statistic about the goal scorer in a football match. (soccer for americans) The table for saving goal statistic has three rows(!). Match_id, player_id and goal_time. This is good data normalization, and minimizes redundancy and make for consistent data. That means the table players_goals need to be linked with other tables that holds data about the specific match and the specific player. This is the reason for create a view.

Don't see the point of this?
There really is one - I promise! By writing a view that is general and display a lot of data, I can write SIMPLE queries to get different results:

1. Last five goal scorers with name of both teams, player name and goal time
SELECT hometeam, awayteam, player_name, goal_time
FROM view_goals_per_game 
ORDER BY kickoff_time DESC

2. Display players with most goals in descending order
SELECT player_name, COUNT(*) as goals
FROM view_goals_per_game
GROUP BY player_id
ORDER BY goals DESC

3. Display all goals by a specific player
 SELECT hometeam, awayteam, player_name, goal_time
FROM view_goals_per_game
WHERE player_id = 10
ORDER BY kickoff_time DESC

4. Find all goals in a specific match
SELECT hometeam, awayteam, player_name, goal_time
FROM view_goals_per_game
WHERE match_id = 837

Does it start to make some sense? Instead of repeating and modifying the same hard-to-grasp code over and over again (see tip #3), use a view to make your life simpler. :)

Hope this has helped someone. I have been thinking about writing a lot of different tips when it comes to MySQL. I've been thinking about writing a guide to joins for example. I really don't know if this interests someone or not.

Hoping others will also share tips and experiences when it comes to MySQL. :)
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#14402 Really Disturbing

Posted by margaux on 1 May 2013 - 4:56 PM

Hey xto, I'm going to try to say this in the nicest way possible -  You're in danger of trying people's patience not because you ask questions, we like questions, but because you ask questions in a way that doesn't provide the information needed to try to answer them.

 

1. please read the forum guidelines - Look for the little grey text bottom right of most pages, labelled Guidelines

2. please post only RELEVANT code and error messages within code tags. We don't need to see the entire output from your error message. It's actually distracting. Use code tags which are on the edit bar and they look like <>

3. post the relevant CODE, you keep posting the error message but not any code.

4. You should start a new thread for each new question. One reason for doing so is that other people with the same question can search and find your thread. If your question is part of another thread, it won't be found and won't help others.

5. You're asking questions that you should be able to solve 1 because the level of  experience for this book expects you know some basic debugging strategies and 2. with a little bit of online searching you would get some pointers as to where to look for the cause of your error.

 

I really shouldn't answer your question given the above but ...

 

somewhere in your code you are referencing an array value using 'sale_price' as the index, which doesn't exist. I'm going to hazard a guess that you have a line that includes $row['sale_price']. From the error dump you posted, you will see there is no index 'sale_price' but there is one named 'price'. Given what info you've provided that's all I can help with. If this doesn't help solve the problem, start a new thread and post the code that is causing the error :)


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#3399 How Much To Charge A Client For A Website?

Posted by chop on 31 August 2011 - 1:23 PM

Once you really understand what the client wants, you can come up with an estimate as to the total number of hours it will take you to complete. Don't make the mistake of getting into a job in which you don't have a complete understanding as to its scope. Otherwise your hours estimate will be way off and you'll be faced with charging the client much more than the estimate or feeling like you were underpaid. So....

WRITE a document that explains exactly what you're going to do based on what the client has expressed they want verbally. Keep in mind that often even the client doesn't know exactly what he wants. So feel free to add in your own suggestions as you do a little market research of other similar sites. GIVE the document to the client. TALK to the client about all the aspects of it. REVISE it as you discuss it until you both have a solid, clear understanding of it. This will prevent other "things" from being thrown into the mix because the client thought they were included from the start.

Big jobs often involve a lot of research of what is needed before anything can begin. IT IS OKAY to bill your client for this time but it should be done on an hourly bases and the bill should be separate from the bill for the website.

The written document that you share with your client might be called a contract, a specification, or a proposal but it should be absolutely clear to both parties before you drive the first nail (including the time line). The exactness of it will make it easy for you to estimate your hours which can be multiplied by what you feel you need to make without you or the client feeling cheated. Make sure that you include any expenses you might incur such as purchase of images etc..This is most important. If the client likes this document then you send a bill for your time, you get paid, and everyone's happy.

I would ask for a retainer of 50% due fairly early in the project in case you do lots of work and the client bails.

How closely you follow this procedure depends on how big the project is. I have had people I know come to me wanting a simple one page site, plain vanilla, and know exactly what they want on it. They just want something for a web presence. I might say, okay, that will cost you $x so please send a check and it will be up in 2 days. Less time involved, less risk, less money so less need for paperwork.

Think also about where you will host it and if you want to charge the client for annual hosting with a little added on for your occasional support. You can get a discount as a reseller on a host, say $50 and charge the client $99/year.

good luck,
chop
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#20055 I'm Having Trouble With Sorting Query Results In Chapter 5... Plz Help!

Posted by Emilie on 30 July 2014 - 1:07 PM

Hello,

 

What is "wrong", according to you?

 

The registration date is the same for all users because you entered all of them at one go into the database, and therefore the timestamp corresponding to NOW() is the same for everyone. Because of that, ordering the results by registration_date DESC has no real meaning.

 

I hope this helps,

 

Emilie


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#14255 Ch 6 'Can I Start Here?'

Posted by Antonio Conte on 22 April 2013 - 5:25 AM

I would really recommend you starting from the beginning with any book about introductory OOP. There's a solid learning curve at first when you switch from procedural to object-oriented programming, and most of that is due to the way you have to think about code. It's a very common mistake to jump straight into code, as many feel they already master coding to some degree. While that's true for many, the basic theory is insanely important, and has very little to do with coding skills. As I said earlier, it's a different approach to coding, not necessarily harder or more advanced.

 

I don't really remember the chapters in this book. You can probably skip some of the first chapters, but make sure you don't skip any OOP theory from the get go. While much of the stuff explained might seem below your current coding level, (and it likely is) it's fundamental in OOP. Make sure to don't blaze through theory because it seems simple. It'll pay of later to focus.

 

What I consider essential for understanding object-orientation:

- Theory about a Class and an Object. Read this thoroughly. Read it more than once.

- Theory about class structures and code planning (i.e what constitutes a class. This is very important and it's not obvious at first)

- Delegation. (A method should do only one specific job)

- Visibility (public, protected, private)

- Class scope and application scope.

- Polymorphism (building of existing classes)

 

Larry is very good at explaining all this, but make sure to take it slow from the start. It will really pay of later. Learning object-orientation is not tricky from a of coding skill level standpoint, but because of the theoretic foundation you need to write good code.

 

Good luck, and have fun. :)


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#14154 Multiple Mysql_Fetch_Array That Drives Me Nuts

Posted by HartleySan on 18 April 2013 - 3:12 PM

Hmmm... I'm not entirely sure what you're going for, but I'm definitely seeing some serious inefficiencies. While I don't know the sizes of your tables (i.e., how many records each one contains), you seem to be grabbing everything from the purchases table, and within that while loop, you are then grabbing everything from the other two tables where a certain value equals a certain value in the purchases table.
 
Also, a lot of the math you're doing (for example, adding up values for the amount of a given order) and formatting of the date can be done on the DB side, which can further speed things up.
In general, I think your goal should be to format all your data exactly the way you want to print it out to the screen by using one query. That may not be possible, and I'm not entirely sure what you want, but I'm thinking that we *may* be able to get everything you want in one query. I will attempt to do so below, but I can't guarantee that it'll work.
 
To start with, I'm trying really hard to figure out what exactly you're going for, but it's a bit abstract with the variables you're using. I'm not sure if you're using those variables on purpose to disguise your code for this thread, or if you're really using those variables in your code, but either way, I would definitely recommend using more logical variable names.
 
Anyway, here's my interpretation of your code:
You're printing out a table of purchase orders. The first column is the row number (which you do not seem to be properly incrementing within the outer while loop). The second column is the ID of a purchase order that a customer has made. The third column is the name of the customer (and it looks like you're storing their first and last name in one column in the customers table, which I would recommend against). The fourth column is the date and time of the purchase. The fifth column is the total amount of the purchase order formatted in dollars and cents. Lastly, I'm not sure what the last two columns are, but they aren't coming from DB data, so I'll ignore those for now.
 
Assuming my interpretation above is correct, I think you need to do an inner join across three tables with the purchases table being the main table. Also, I think you need to group your purchases together by the purchase ID, so that you can use an aggregate function to add up the price of the individual items within each specific order.
Does that make sense?
 
Anyway, here's the query that I'm *thinking* will work (but I can't guarantee that it does or that it's what you want):
SELECT c.cust_id, c.name AS cust_name, p.po_id AS order_num, p.cust_id, DATE_FORMAT(p.timestamp, '%m %d, %Y') AS date, o.po_id, SUM(o.delivered * o.srp) AS amount
FROM customers AS c, purchases AS p, po_content AS o
WHERE c.cust_id = p.cust_id AND p.po_id = o.po_id
GROUP BY o.po_id
ORDER BY p.timestamp ASC
LIMIT $start $display;
 
A few notes about the query:
1) For your query, a join is essential. Specifically, two inner joins on the purchases table is what you need. Joins are tricky at first, but they're essential for most DBs, so I'd recommend studying up on them.
 
2) Only select the columns you need. Using SELECT * for three separate queries is getting you a lot of data you don't need, and is very inefficient.
 
3) Use aliases (e.g., "AS c", "AS p", etc.) on the tables to make typing out the query shorter and easier. Also, aliases are essential for being able to easily reference the results of aggregate functions, formatted, dates, etc.
 
4) Format the timestamp on the SQL side using the DATE_FORMAT function. It's faster and easier. Also, give the formatted date an alias to make it easier to access on the PHP side. Here's more info on the DATE_FORMAT function:
 
5) I'd calculate the total amount of each order on the SQL side. To do so, you need to use the SUM aggregate function, and also use the GROUP BY clause to group your results together by order number so that you are adding up the correct grouping of items. Also, I'd assign an alias to the result of the SUM function.
 
6) The "ASC" part of the query is not necessary, since that's the default ordering. I left it anyway to avoid any further confusion.
 
7) I used "o" as the alias of the po_content table, as it seems like a table of orders to me.
 
That will hopefully handle the query side of things.
Unfortunately, I think there are some other issues with your code as well:
1) You're not incrementing $rownum in the while loop.
 
2) You're assigning your $bgcolor value to the entire table, not individual table rows. Also, I'm pretty sure the resulting HTML will be syntactically invalid and not work.
 
3) You're creating a new table each time through the while loop.
 
4) You're putting a div within a td for the total, which I wouldn't do.
 
Point being, without sounding too harsh, I think your code has some serious issues and needs some re-working. I get the feeling that you might be getting a bit too ambitious about your personal project without first understanding all the basics you need.
I don't mean to say that you shouldn't be ambitious, but I think you should probably go back to the book for a bit and bone up on queries with joins, HTML and PHP syntax, as well as think more about the logic of your while loop and the type of HTML that it is creating.
 
Anyway, below, I'm going to present the PHP I would use for your situation. Again, please keep in mind that I'm doing my best to piece together exactly what you want (and I'm not entirely sure), so I could be way off on this.
// I'm assuming that $agent and $encoder are already defined above.
 
$row_num = 1;
 
$total = 0;
 
$bg_color = '#FFF';
 
$q = "SELECT c.cust_id, c.name AS cust_name, p.po_id AS order_num, p.cust_id, DATE_FORMAT(p.timestamp, '%m %d, %Y') AS date, o.po_id, SUM(o.delivered * o.srp) AS amount FROM customers AS c, purchases AS p, po_content AS o WHERE c.cust_id = p.cust_id AND p.po_id = o.po_id GROUP BY o.po_id ORDER BY p.timestamp ASC LIMIT $start $display;";
// I'm assuming that $start and $display are already defined above.
 
$r = mysqli_query($dbc, $r);
// I am assuming that $dbc is already defined above. You also seem to have omitted this argument in your code.
 
echo '<table class="order_details">';
// I'd use CSS to properly format the table instead of the inline attributes you're using.
// As such, I have assigned a class to the table for that exact reason.
// Also, your table doesn't have any headers, but you may want to add them along with thead, th, tbody, and tfoot tags.
 
while ($row = mysqli_fetch_array($r, MYSQLI_ASSOC)) {
  
  echo '<tr style="background-color: ' . $bg_color . ';">
  
  <td>' . $row_num . '</td>
  
  <td>' . $row['order_num'] . '</td>
  
  <td>' . $row['cust_name'] . '</td>
  
  <td>' . $row['date'] . '</td>
  
  <td>' . number_format($row['amount'], 2) . '</td>
  
  <td>' . $agent . '</td>
  
  <td>' . $encoder . '</td>
  
  </tr>';
  
  $row_num++; // Don't forget to increment this.
  
  $total += $row['amount']; // This is the summation of the unformatted amounts, which could cause issues.
  
  $bg_color = ($row_num % 2 === 0) ? '#F3F3F3' : '#FFF'; // Ternary operation for brevity
  
}
 
echo '<tr style="background-color: ' . $bg_color . ';">
 
<td colspan="4" class="total_row">Total</td>
 
<td>' . number_format($total, 2) . '</td>
 
</tr>';
// Formatted to line up with the amount column.
// Also, note that I handled the total the same way you did, but if you calculate the total on the
// unformatted amount values, then you may get a discrepancy in which the amounts don't add up to the total.
// Also, again, I'd use CSS (not inline HTML) to align "Total" to the right.
// Lastly, you may want to put the total in a tfoot element.
 
Well, I think that's about it.
After all this writing, I really hope that I got close to what you wanted, and that this post is of some use.
Please let me know.
Thanks.

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#12357 Geting Url Form Users And Validate Them

Posted by HartleySan on 16 January 2013 - 3:14 AM

Edward, a little bit less of a Yii sales pitch would have been nice.

thara, you said you tried to use FILTER_VALIDATE_URL in PHP. Did it work? It should.
I would use FILTER_VALIDATE_URL, if possible, and as you suggested, I might omit the protocol entry part, as all links should probably be either http or https.
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#12215 When Js Isn'T Available.

Posted by HartleySan on 8 January 2013 - 6:24 PM

Unfortunately, that's the nature of the beast. With JS disabled, you lose a lot of functionality, and certainly, that's one if the downsides of relying on JS libraries to do all the work for you.

Obviously, you'd most likely want the non-JS version of your site to mirror the JS version as much as possible, but that's not always possible/practical. With that said, I think Larry says in one of his books somewhere, as long as the non-JS site works and gets the user the information necessary, that's good enough (even if the site looks/behaves like crap). I more or less agree with this, but obviously, if given the time, making a non-JS version of your site that is similar in appearance and functionality never hurts.

Here's my main COA when designing a site to have both a non-JS and JS version:

1) Plan, plan, plan! In regards to the above, this means trying to minimize JS as much as possible while still giving a good experience. By minimizing the JS used, the two sites will be more similar and it'll be less work to get both working correctly.
Unfortunately, if you're locked into something like Twitter bootstrap, then you might have your work cut out for you in this regard. This is one of the main things I don't like about a lot of JS libraries these days: they use JS for a lot of things you don't need JS for; nowadays, you can do a lot with HTML and CSS alone.

2) Use noscript tags for content that is required as a replacement for JS-generated content when JS is disabled. For example, you might make a new, second menu within noscript tags to handle navigation when your Twitter bootstrap menu is busted because JS is disabled.

3) For content that requires JS, either generate the markup for it using JS, or use CSS to hide the content by default, and then use JS to display it when the page first loads. If you don't do one or the other, then you will get JS-dependent content appearing on the screen, which is useless and confusing to users who have JS disabled (ala your Twitter menu).

4) With all the above in mind, develop the entire site first without using any JS. This will serve as a solid base. After that, add JS functionality as needed, keeping all the above in mind. Because this may be time-consuming, you may want to consider launching with the non-JS version only (since that should be enough to do whatever on your site), and then adding JS functionality here and there post-launch.

And that's basically it. Obviously, depending on the scope/size of your site, this may add considerable time to development, but that's the price you pay if you want a decent non-JS site. I think a log of people these days don't find it worth the effort to do all of the above though (so they don't).

And keep in mind that there are other things to consider these days as well. For example, "mobile first", which is a good guiding principle and strongly emphasizes loading content non-essential for the mobile version using JS. These sorts of considerations may very well conflict with designing a good non-JS site, so please keep that in mind.

Well, I've blabbered on long enough, and I probably mentioned a bunch of stuff you already knew, but there ya go.

- The other Jonathan (with a slightly different spelling)
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#11560 Simple Question On Php Form Validation...

Posted by HartleySan on 8 December 2012 - 12:32 AM

When you execute the header(Location: 'somelocation.php#contact'); line, you're reloading the page, which causes the $_POST array, $errors variable, etc. to no longer exist. This essentially amounts to the same thing as having never performed any validation at all (and thus the $errors variable not existing, which is why your "Please fix the errors" line is never printed out).

A better solution would be to put the anchor jump (i.e., the fragment part in the URL after the number sign (#)) in the URL specified for the action attribute of the contact form. For example, if the following is the opening tag for your contact form:

<form action="somelocation.php" method="post">

Then change it to the following:

<form action="somelocation.php#contact" method="post">

Of course, this assumes that somelocation.php refers to the original page the form is on (which seems to be the case according to what you said).
By doing the above, you can very easily get the jump you want and still properly validate everything.

In terms of outputting a thank you message upon successful validation, I'd do something like the following:

if (!$errors) {

  // Validation was successful. Output a thank you message.

} else {

  // Either there was an error or this is the first time the page was loaded.
  // Load the page with the form and any necessary sticky values and error messages.

}

Hope that helps.
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#11512 Exception Handling For Flow Control?

Posted by Antonio Conte on 6 December 2012 - 6:46 PM

It depends. More often than not, application breaking errors should throw exception. As an example, an invalid date, improper email addresses or bad zip codes could benefit from throwing exceptions. The reason for that is data integrity. A class/function could very well be dependent of having valid data on a special format to be able to perform actions/calculations of it.

You'll often see people defining their own exceptions like so. In this example we have a example class for sending email. It's no point sending an email to "111lol!", so then it's good practice to throw an exception. (

class Email
{
public function send( $email )
{
    if (! filter_var($email, FILTER_VALIDATE_EMAIL))
    {
	    throw new InvalidEmailAddressException("Invalid email adress provided.");
    }
}

// Email exception
class InvalidEmailAddressException extends Exception
{
    public function __construct($message) { parent::__construct($message); }
}

Hope that gives you a general idea. Short answer would be this: for "checking values", use return values. User::add() could return true/false on how the adding went. For invalid values that could break classes/methods, throw exceptions.
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#13394 Pls Help Need Urgent Help. The .Inc Extension. Chapter 11

Posted by margaux on 11 March 2013 - 4:45 AM

It's difficult to debug when the code is presented in this way. Please would you use code tags.

 

At first look, no error immediately jumps out. Which line is line 46? Look at that line and the few lines before it.

 

Probably not causing this error but it looks like you may have a typo on the tablename in the SELECT statement - users instead of usera?


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