Prepare for the CompTIA Network+ exam by learning how to troubleshoot, configure, and manage both wired and wireless networks.
PHP
120K
Solutions
33K
Contributors
PHP is a widely-used server-side scripting language especially suited for web development, powering tens of millions of sites from Facebook to personal WordPress blogs. PHP is often paired with the MySQL relational database, but includes support for most other mainstream databases. By utilizing different Server APIs, PHP can work on many different web servers as a server-side scripting language.
Share tech news, updates, or what's on your mind.
Join us in celebrating longtime user Rowby Goren for his great contributions of engaging with other users on site. We explore his method for posing questions that are likely to yield a solution, and take a look at how his career transformed from a Hollywood writer to a website entrepreneur.
1 Comment
This article demonstrates a very simple pattern for creating a WordPress plugin that displays and processes a form. The form is activated by a shortcode and includes server side validation of the data .
Laravel is the most sought after web development framework. It comes with ample amount of features that make it easy for developers to work around it. Know about its features in detail.
I recently worked on a Wordpress site that utilized the popular ContactForm7 (https://contactform7.com/) plug-in that only sends an email and does not save data. The client wanted the data saved to a custom CRM database. This is my solution.
This holiday season, we’re giving away the gift of knowledge—tech knowledge, that is. Keep reading to see what hacks, tips, and trends we have wrapped and waiting for you under the tree.
The title says it all. Writing any type of PHP Application or API code that provides high throughput, while under a heavy load, seems to be an arcane art form (Black Magic). This article aims to provide some general guidelines for producing this type of code.
It’s a season to be thankful, and we’re thankful for users like you who engage on site, solve technology problems, and network with others in the industry. What tech are we most thankful for? Keep reading.
There are times when I have encountered the need to decompress a response from a PHP request. This is how it's done, but you must have control of the request and you can set the Accept-Encoding header.
Comment Utility
You're right, and I'm sorry.
I was frustrated from that post that it bothered me that the answer seemed simple.
I've modified the post to be neutral and answer the question only.
Regards,
Shai
I was frustrated from that post that it bothered me that the answer seemed simple.
I've modified the post to be neutral and answer the question only.
Regards,
Shai
Become a Certified Penetration Testing Engineer
This CPTE Certified Penetration Testing Engineer course covers everything you need to know about becoming a Certified Penetration Testing Engineer. Career Path: Professional roles include Ethical Hackers, Security Consultants, System Administrators, and Chief Security Officers.
This article discusses how to implement server side field validation and display customized error messages to the client.
Many old projects have bad code, but the budget doesn't exist to rewrite the codebase. You can update this code to be safer by introducing contemporary input validation, sanitation, and safer database queries.
Hi many thanks for your post is really interesting, is there any way to do the same with procedural prepared statement? Many thanks
Comment Utility
PHP.net has an article about stored procedures and PDO: http://php.net/manual/en/p
3 proven steps to speed up Magento powered sites. The article focus is on optimizing time to first byte (TTFB), full page caching and configuring server for optimal performance.
Introduction
This article is intended for those who are new to PHP error handling. It addresses one of the most common problems that plague beginning PHP developers: effective error visualization.
PHP error handling is well-documented in the online man pages, but the documentation often eludes beginners, who are trying to learn PHP by copying examples they found on the internet. Copying the code without understanding the code is an antipractice, and there are so many bad PHP examples out there, it can sometimes be difficult to find good ones! This article will help you get the most, quickly and easily, out of PHP's basic error handlers. You can get excellent error information, informative and well-targeted, by just following a few simple examples. So stop copying those obsolete internet examples, and instead make a few "teaching examples" for your own library. By the time you've finished this article, you will have some great insights into how to diagnose the most common errors quickly and find good solutions.
What's Covered Here
PHP has unlimited opportunities for errors, but in practice only a few things are needed to get good diagnostics. You need to be able to see the errors in PHP and you need to …
This article is intended for those who are new to PHP error handling. It addresses one of the most common problems that plague beginning PHP developers: effective error visualization.
PHP error handling is well-documented in the online man pages, but the documentation often eludes beginners, who are trying to learn PHP by copying examples they found on the internet. Copying the code without understanding the code is an antipractice, and there are so many bad PHP examples out there, it can sometimes be difficult to find good ones! This article will help you get the most, quickly and easily, out of PHP's basic error handlers. You can get excellent error information, informative and well-targeted, by just following a few simple examples. So stop copying those obsolete internet examples, and instead make a few "teaching examples" for your own library. By the time you've finished this article, you will have some great insights into how to diagnose the most common errors quickly and find good solutions.
What's Covered Here
PHP has unlimited opportunities for errors, but in practice only a few things are needed to get good diagnostics. You need to be able to see the errors in PHP and you need to …
Comment Utility
Thanks, Martin.
Some time ago when I published articles, there was a cascade of approvals - something like "It's OK" then "It's good" then "It's really good" and each of these approvals gave some more points as well as comments about how the article can be made better. Does E-E still do that?
Some time ago when I published articles, there was a cascade of approvals - something like "It's OK" then "It's good" then "It's really good" and each of these approvals gave some more points as well as comments about how the article can be made better. Does E-E still do that?
Since pre-biblical times, humans have sought ways to keep secrets, and share the secrets selectively. This article explores the ways PHP can be used to hide and encrypt information.
Comment Utility
can a file be encrypted with OpenSSL as it is being streamed in so it is not first saved in plaintext form
This article discusses four methods for overlaying images in a container on a web page
Nothing in an HTTP request can be trusted, including HTTP headers and form data. A form token is a tool that can be used to guard against request forgeries (CSRF). This article shows an improved approach to form tokens, making it more difficult to use "screen scrapers" to attack web forms.
Active 1 day ago
it's a great article. I wish I had read it earlier.
Thank you very much Ray Paseur
Thank you very much Ray Paseur
HTML5 and CSS3 Fundamentals
Build a website from the ground up by first learning the fundamentals of HTML5 and CSS3, the two popular programming languages used to present content online. HTML deals with fonts, colors, graphics, and hyperlinks, while CSS describes how HTML elements are to be displayed.
Have you tried to learn about Unicode, UTF-8, and multibyte text encoding and all the articles are just too "academic" or too technical? This article aims to make the whole topic easy for just about anyone to understand.
Comment Utility
Nice article!
I'm one of those poor souls who has to write cross-platform C++ code and the headaches involved in getting Unicode encoding working in a cross platform way is a nightmare. In general, we stick to UTF8 right up until we hit the system functions. On *nix platforms UTF8 works fine, on Windows one has to convert to UTF16. It's a bit of a pain, because there is a little inefficiency in doing this but it's normally not enough to cause concern.
What doesn't help is the fact Microsoft continuously refer to UTF16 as Unicode and anything else as ANSI. This has confused a lot of Windows programmers into thinking if it's a 16 bit data type it must be Unicode and if it's an 8 bit data type it's not. Ironically, Windows has no native support for UTF8 at the API level, even though it does have a UTF8 code page! I wish someone would welcome Microsoft into the 21st Century :)
UTF8 is really the only portable encoding format and for my money it's the encoding format I'd go for every time. Anyone interested in Unicode transformation and encoding, either because they are an engineer or they are a masochist, should also find the following resource really very useful and a nice compliment to this well written article.
http://utf8everywhere.org/
Thanks, Gonzo.
I'm one of those poor souls who has to write cross-platform C++ code and the headaches involved in getting Unicode encoding working in a cross platform way is a nightmare. In general, we stick to UTF8 right up until we hit the system functions. On *nix platforms UTF8 works fine, on Windows one has to convert to UTF16. It's a bit of a pain, because there is a little inefficiency in doing this but it's normally not enough to cause concern.
What doesn't help is the fact Microsoft continuously refer to UTF16 as Unicode and anything else as ANSI. This has confused a lot of Windows programmers into thinking if it's a 16 bit data type it must be Unicode and if it's an 8 bit data type it's not. Ironically, Windows has no native support for UTF8 at the API level, even though it does have a UTF8 code page! I wish someone would welcome Microsoft into the 21st Century :)
UTF8 is really the only portable encoding format and for my money it's the encoding format I'd go for every time. Anyone interested in Unicode transformation and encoding, either because they are an engineer or they are a masochist, should also find the following resource really very useful and a nice compliment to this well written article.
http://utf8everywhere.org/
Thanks, Gonzo.
Introduction
JSON is an acronym for JavaScript Object Notation. It is a text-string data transport mechanism, capable of representing simple or complex data structures in a consistent and easy-to-read manner. Similar in concept to XML, but more efficient and more widely supported, JSON has become the dominant technology for use in AJAX applications, APIs, and other data interchange applications where data structure and data elements must be communicated between applications and web services.
JSON is frequently found in combination with RESTful APIs, where XML has rightly fallen into disuse. This article will examine some of the ways XML and JSON are similar and different, and will show ways of using JSON to our advantage.
Some code examples will show how to create and interpret JSON strings, and detect JSON errors.
A Bit of Test Data
Since the most important thing a programmer can have is a good test case, let's start with some good test data. Here is the information we will use for all of our code examples. This information will represent people, giving their names and ZIP codes. While the example is truly minimalist, it's sufficient to illustrate the principles.
A Bit of Test Data Organization
Both XML and JSON can represent the data structure. Here is how our data will be organized.
The Old School Way: XML
XML, or Extensible Markup Language, is a text-string data transport mechanism. It was popularized in the 1990s when SOAP…
JSON is an acronym for JavaScript Object Notation. It is a text-string data transport mechanism, capable of representing simple or complex data structures in a consistent and easy-to-read manner. Similar in concept to XML, but more efficient and more widely supported, JSON has become the dominant technology for use in AJAX applications, APIs, and other data interchange applications where data structure and data elements must be communicated between applications and web services.
JSON is frequently found in combination with RESTful APIs, where XML has rightly fallen into disuse. This article will examine some of the ways XML and JSON are similar and different, and will show ways of using JSON to our advantage.
Some code examples will show how to create and interpret JSON strings, and detect JSON errors.
A Bit of Test Data
Since the most important thing a programmer can have is a good test case, let's start with some good test data. Here is the information we will use for all of our code examples. This information will represent people, giving their names and ZIP codes. While the example is truly minimalist, it's sufficient to illustrate the principles.
firstName lastName zipCode
John Doe 20007
Mary Doe 20016
A Bit of Test Data Organization
Both XML and JSON can represent the data structure. Here is how our data will be organized.
People (with a date attribute)
|_ Person
|_firstName
|_lastName
|_zipCode
The Old School Way: XML
XML, or Extensible Markup Language, is a text-string data transport mechanism. It was popularized in the 1990s when SOAP…
Active today
Ray,
Great article (as always) :). I just wanted to address the "Using JSON Strings in JavaScript" section of your article.
I'd like to see the distinction between JavaScript and jQuery/AngularJS to show that jQuery & AngularJS are frameworks of the JavaScript language. In otherwords, they are just JavaScript. They do not implement their own version of the ECMA-262 standards. Node.js on the other hand DOES have its own version but being only a server side language, that's a different story.
On another note, JSON in the browser still needs to be decoded from a string to be a useful JavaScript native object. Any data that PHP returns in JSON format will need to be decoded using the JSON.parse() native JavaScript function. jQuery will do this automatically when the getJSON() or ajax() with the dataType set to "json" but vanilla JavaScript will not. For your reference: http://www.w3schools.com/js/js_json.asp
Following on from this, the example you go on to give isn't a string, but a JS object. I'd like to see an example of using the native functions for converting JSON strings to objects as indicated here: http://www.w3schools.com/js/js_json.asp
Great article (as always) :). I just wanted to address the "Using JSON Strings in JavaScript" section of your article.
I'd like to see the distinction between JavaScript and jQuery/AngularJS to show that jQuery & AngularJS are frameworks of the JavaScript language. In otherwords, they are just JavaScript. They do not implement their own version of the ECMA-262 standards. Node.js on the other hand DOES have its own version but being only a server side language, that's a different story.
On another note, JSON in the browser still needs to be decoded from a string to be a useful JavaScript native object. Any data that PHP returns in JSON format will need to be decoded using the JSON.parse() native JavaScript function. jQuery will do this automatically when the getJSON() or ajax() with the dataType set to "json" but vanilla JavaScript will not. For your reference: http://www.w3schools.com/js/js_json.asp
Following on from this, the example you go on to give isn't a string, but a JS object. I'd like to see an example of using the native functions for converting JSON strings to objects as indicated here: http://www.w3schools.com/js/js_json.asp
Comment Utility
Hey, Rob. Thanks for your comments. Why not add your clarification examples to the comment thread here, or post a new article about this? Especially if any of my old code and data examples are overtaken by current events... technology is always advancing!
Does the idea of dealing with bits scare or confuse you? Does it seem like a waste of time in an age where we all have terabytes of storage? If so, you're missing out on one of the core tools in every professional programmer's toolbox. Learn how to do amazing, modern things with bits!
Active 1 day ago
@philkryder - The impact is going to be different depending on the application. For example, let's say that you do have this situation where you're dealing with 20 million 15-byte strings (roughly 286 megabytes).
If you're dealing with a database, then typically you're in a client/server setup, so the client needs the data locally in order to do any viewing or processing (this can be expanded also to a scenario where you've got DB Server -> Web Server -> End User, and data has to be transferred twice - and that's just basic setups).
Typically, the data's going to be transmitted over a TCP/IP network connection, so you're also adding about 8 megs of TCP overhead for 300,000,000 bytes (versus 2 megabytes for 80,000,000 bytes). You also have overhead of the structure containing/defining the data, plus any extra identifying data, but we'll set that aside for now.
So let's say that the database server has all the resources it needs to send all the data across to the client. On a LAN, it might not take too long either way, but you'll still notice a significant difference between transferring 78-ish megs vs 294-ish megs.
If you're dealing with a situation where you transfer that over a broadband connection of some kind, the difference will be even larger.
So the majority of the time, your "extra time" is going to be found in the data transfer, since that's often the slowest point. For the sake of having some example numbers, let's say that we're transferring over a 60Mbps connection, so we're looking at anywhere from 30 seconds - 45 seconds to download a roughly-300 meg payload, and 10-15 seconds to download a roughly 80-meg payload.
We'll say that we can save about 20-30 seconds in transfer time.
Now let's say the client app finally has the data in memory. It probably needs to store it somewhere, so there's some kind of structure involved, which also means an extra % of overhead storage in memory. Let's say you have a C# app using a DataTable structure. A string column in a DataTable takes up a LOT more memory per row than a long column. I don't have hard numbers in front of me, but I did have a project once where I hadn't defined my column type and I was accidentally storing small integers as a string. When I fixed the problem with a byte type definition on the field, memory usage dropped by several hundred megabytes.
So now we've got a client app with the data in memory. What's the next step?
If we're displaying the data on-screen, then chances are that you're probably only converting a handful of records at a time - maybe 200 at most. The time it takes to convert 200 longs into string is around 0.001 seconds each time (just a rough test on my end).
But let's say you want to convert those 20 million numbers into 20 million entries all at once to be written to a file. Let's say that looping through 20 million records in memory takes a full 3 seconds, with absolutely no processing at all, so it wouldn't matter if the numbers were already converted or not - 3 seconds is the starting baseline. Your question is then - how much ADDITIONAL time would it take to convert 20 million numbers? A rough test on my machine shows about 40 seconds, and of course, that's going to depend on processor power. Many machines might be even slower.
So now we have some example numbers.
You have about 20-30 seconds of savings on the transfer side. If you were to turn around and convert all of those to strings immediately and write them to a file, then you're probably looking at a speed LOSS of roughly 10 seconds. Of course, this also doesn't take anything else into consideration (the value of bandwidth pipes / network saturation / memory / likelihood of this scenario / scalability across multiple clients / etc).
For displaying the data on-screen, you have about 20-30 seconds of savings on the transfer side, and virtually no time spent on conversion since you're not doing them all at once. The client's not going to notice a split-second of extra time every time they move to a new page of results.
Either way, there is a LOT of extra value in more efficient storage. There will always be some scenarios where it doesn't make sense to compact everything, but that's where being a good programmer comes into the picture and understanding the business case and how it translates into data flows and the value of each resource involved, and how that multiplies with concurrent load.
If you're dealing with a database, then typically you're in a client/server setup, so the client needs the data locally in order to do any viewing or processing (this can be expanded also to a scenario where you've got DB Server -> Web Server -> End User, and data has to be transferred twice - and that's just basic setups).
Typically, the data's going to be transmitted over a TCP/IP network connection, so you're also adding about 8 megs of TCP overhead for 300,000,000 bytes (versus 2 megabytes for 80,000,000 bytes). You also have overhead of the structure containing/defining the data, plus any extra identifying data, but we'll set that aside for now.
So let's say that the database server has all the resources it needs to send all the data across to the client. On a LAN, it might not take too long either way, but you'll still notice a significant difference between transferring 78-ish megs vs 294-ish megs.
If you're dealing with a situation where you transfer that over a broadband connection of some kind, the difference will be even larger.
So the majority of the time, your "extra time" is going to be found in the data transfer, since that's often the slowest point. For the sake of having some example numbers, let's say that we're transferring over a 60Mbps connection, so we're looking at anywhere from 30 seconds - 45 seconds to download a roughly-300 meg payload, and 10-15 seconds to download a roughly 80-meg payload.
We'll say that we can save about 20-30 seconds in transfer time.
Now let's say the client app finally has the data in memory. It probably needs to store it somewhere, so there's some kind of structure involved, which also means an extra % of overhead storage in memory. Let's say you have a C# app using a DataTable structure. A string column in a DataTable takes up a LOT more memory per row than a long column. I don't have hard numbers in front of me, but I did have a project once where I hadn't defined my column type and I was accidentally storing small integers as a string. When I fixed the problem with a byte type definition on the field, memory usage dropped by several hundred megabytes.
So now we've got a client app with the data in memory. What's the next step?
If we're displaying the data on-screen, then chances are that you're probably only converting a handful of records at a time - maybe 200 at most. The time it takes to convert 200 longs into string is around 0.001 seconds each time (just a rough test on my end).
But let's say you want to convert those 20 million numbers into 20 million entries all at once to be written to a file. Let's say that looping through 20 million records in memory takes a full 3 seconds, with absolutely no processing at all, so it wouldn't matter if the numbers were already converted or not - 3 seconds is the starting baseline. Your question is then - how much ADDITIONAL time would it take to convert 20 million numbers? A rough test on my machine shows about 40 seconds, and of course, that's going to depend on processor power. Many machines might be even slower.
So now we have some example numbers.
You have about 20-30 seconds of savings on the transfer side. If you were to turn around and convert all of those to strings immediately and write them to a file, then you're probably looking at a speed LOSS of roughly 10 seconds. Of course, this also doesn't take anything else into consideration (the value of bandwidth pipes / network saturation / memory / likelihood of this scenario / scalability across multiple clients / etc).
For displaying the data on-screen, you have about 20-30 seconds of savings on the transfer side, and virtually no time spent on conversion since you're not doing them all at once. The client's not going to notice a split-second of extra time every time they move to a new page of results.
Either way, there is a LOT of extra value in more efficient storage. There will always be some scenarios where it doesn't make sense to compact everything, but that's where being a good programmer comes into the picture and understanding the business case and how it translates into data flows and the value of each resource involved, and how that multiplies with concurrent load.
Comment Utility
Excellent article! The only thing I would have included would be a small section on Endianness (Big Endian vs. Little Endian).
PHP
120K
Solutions
33K
Contributors
PHP is a widely-used server-side scripting language especially suited for web development, powering tens of millions of sites from Facebook to personal WordPress blogs. PHP is often paired with the MySQL relational database, but includes support for most other mainstream databases. By utilizing different Server APIs, PHP can work on many different web servers as a server-side scripting language.
Top Experts In
PHP
-
1
Chris Stanyon48,384 points -
2
gr8gonzo18,109 points -
3
Julian Hansen11,779 points -
4
David Favor8,726 points -
5
Scott Fell, EE MVE7,030 points -
6
Rob5,150 points -
7
Aaron Street4,400 points -
8
Martyn Spencer3,100 points -
9
ste5an3,050 points -
10
Ray Paseur3,027 points -
11
lenamtl2,900 points -
12
Steve Bink2,600 points -
13
Terry Woods2,555 points -
14
Dr. Klahn2,550 points -
15
Mark Wills2,250 points -
16
shobinsun2,250 points -
17
jsaun2,050 points
-
18
pcelba2,050 points -
19
ddantes2,000 points
-
20
Jeffrey Dake1,550 points -
21
Swatantra Bhargava1,550 points -
22
Black Sulfur1,550 points
-
23
bbao1,333 points -
24
John Tsioumpris1,333 points -
25
David S.1,300 points -
26
Prabhin MP1,300 points