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Pagination using mysql and php

Yes, there are many solutions. If with "recent entries" you mean "sorted by date" (or with sequential indexed IDs), all you need to do is : Define a variable called $last_id = 0; Use a SELECT ...
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3 votes

Extra feature to send receipts - PHP Mailer not connecting

The problem is really about host(smtp.fas.harvard.edu), I had the same problem and here is my decision: I created a new mailbox at gmail, and used it like this: /*Sends a message of $body with ...
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3 votes
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How Does extract() Work in PHP?

I just wanna make sure, does extract() declare these variables as global variables? Not necessarily. The description of extract() reads, "Import variables from an array into the current symbol table."...
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3 votes

How to link submit button with the <select> list in HTML?

You can achieve that using JavaScript: <div> <h1>SELECT A TOPIC</h1> <select id="select"> <option value="physics">physics</option> <option value="...
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3 votes

phpMyAdmin: "mysql extension missing" error

We all know that phpMyAdmin can be flaky sometimes. Unfortunately, I can't tell you how to fix it -- but I can tell you how to use mysql50 shell from the command line. Try stuff like this: mysql50 ...
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2 votes
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How Does PHP Construct Variables and Store Data in Them?

Toward the end of the last century (early 1990's) a common way for web servers to talk to programming languages was by using the Common Gateway Interface (CGI). CGI is very simple and works in a way ...
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2 votes

How Does PHP Construct Variables and Store Data in Them?

When we submit form data to a URL or a page using either of these methods (i.e., GET and POST), how does this web page receive this data underneath the hood? GET and POST are two request methods of ...
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2 votes
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How to create a drop-down menu that contains the stocks that has as options?

First, for closed tags, if you open a tag, you should close it. I see you're not closing the <select> tag. More information about that tag maybe found here. Also, you have </div> within ...
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2 votes
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How to determine how much cash a user has in C$50 Finance's portfolio.php

Yes your logic is correct, and this is exactly the way the world works. Say I have $20. I buy a diamond for $10. So now I have $10 left. In a week from now, the same diamond, costs $5. But I still ...
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2 votes
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How to Correctly Submit Form Data Using GET?

If https://www.google.com/search?q=cs50 submits form data using GET to search, what is search? search is just a path that Google's web servers use as an entry point into the search engine. Behind ...
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2 votes
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Question about "echo", "print", "printf" in php

here's a good link which shows you the differences: http://www.nutt.net/2004/12/09/php-benchmarking-echo-vs-print-vs-printf/
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  • 425
2 votes

pset8 (mashup) - Inserting $places variable into configure function in scripts.js

I figured it out. <%= ... %> is indeed the way you pass in arguments to _.template. When I watched the video in the problem set again the prof mentioned how this code operates similarly to the "%i" ...
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2 votes
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register php pset7 query to INSERT do not work

Such a subtle thing. Your are inserting 3 columns (username, hash, cash). The computer thinks you are sending 4 values because of the comma in your cash amount. VALUES(?, ?, 10000,00)
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2 votes
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When I run my apache50 server at ~/workspace/pset7/public why does login.php files open?

From the pset instructions: Know that index.php is the file that’s loaded by default when you visit a URL like https://ide50-username.cs50.io/. ...which calls (redirects to) login.php (via ...
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2 votes

include 'file.php' does not seem to work

You've probably gotten used to using #include statements in C. The equivalent function in PHP is require(). If you have access to pset7 or pset8, just look at the distribution code provided. You'll ...
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2 votes
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syntax error, unexpected 'for' T_FOR

Not all of them! $alphacount = 0 :)
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2 votes

cs50::init(_DIR_."/../config.json") pset7

To answer the specific question from your comment "why is :: used?" From the config section of the spec (That :: syntax just means that init is "inside of" an "object" called CS50. An object in ...
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1 vote
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Looking at the course, could I use PDO instead of mysql?

as you reach pset7, the first pset that you are going to interact with a database in it, you won't have to write your own code to connect with your database. instead, there is a query function ...
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1 vote
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PSET8 import undefined offsets and fatal error

The problem is your input data. Your query is expecting 12 values on every line. The first line in your example has 9. You "lost" the blank columns from the text file, presumably when you converted ...
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1 vote
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PSET8 import fatal error

The problem is your insert query. You are inserting 12 columns, you have 12 ? placeholders, but you are sending 13 arguments. Also, beware: implode returns a string. So you $str_values[0] et. al. ...
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1 vote

Printing from SQL in PHP

recall that, assuming the query is syntactically correct, query returns an array of the resulting rows (if any) or an empty array otherwise. try print_r'ing $comment to learn about the structure of ...
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1 vote
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pset7 php generated html appearing above CS50 finance header

Ignore this, It was actually fixed very easily by switching the order of the render function and the array loop. Doh!
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1 vote
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Escaping Characters in PHP

the first argument that preg_match takes according to the documentation is a pattern. that is, a regular expression to test $destination against in this case. the forward slashes (i.e., /) at the ...
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1 vote

Accessing information from PHPmyadmin using Javscript

This is the answer from Kareem's link. Please do not vote on this. I just want to take this answered question out of the unanswered list. There are actually several approaches to do this. Some ...
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1 vote
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Finance: Buy/Sell does not insert into MySQL history table

Try checking your index+ link on the Structure view. I deleted all my unique and primary keys, as well as any links to other tables. This solved the problem..thanks to Kareem .. and, I apologise for ...
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  • 28
1 vote

Array in php vs R (pset7 sell.php)

Just like _POST your positions is an associative array. Just as you get $_POST["symbol"] you get $positions["price"]. If I understood correctly you want to do something like the following <?php ...
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  • 7,326
1 vote
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CSS Table Gradient Not Working

I made something simple but I think you can tinker further on your own: grad.html <!DOCTYPE html> <html> <head> <link rel="stylesheet" type="text/css" href="style....
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1 vote
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Path to PHP Interpreter

If I understand correctly you mean the path to php interpreter so that to use a #! to make it executable. It's #!/usr/bin/env php.
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  • 7,326
1 vote

Path to PHP Interpreter

I think the simplest answer is php <filename>. So if you have a php file called hello.php that looks like this: <?php printf("Hello, world!\n"); ?> you would run php hello.php and you'd ...
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1 vote
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How to Redirect Only When a User Clicks Ok on a Popup?

If you want to use the redirect() function provided in pset7 I'm not sure how, but in general you can do it like so: echo "<script type='text/javascript'> if (confirm('Want to redirect?'...
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