PHP stands for personal home page and is a scripting language. Its interpreter is available free and mostly used on Linux or Windows servers. Personal home pages were its former name, now it is known by the name of hypertext processor which is an acronym of the recursive word.
PHP syntax is pretty easy and estimated about the programmers who can write their first program by searching on Google. It reproduces code junks and developers usually asked to be code reusability and optimization in their projects. Every programmer has its own way of programming but some common mistakes which are happened by every programmer are explained below. Such mistakes are easy to avoid and easy to handle. After writing your php code make sure your code is clean, reusable and smoothly running against these blunders.
Missing A Semicolon After WHILE()
One semi-colon can create troubles for the whole program to debug and execute without reporting an error. Such errors quietly fall into the silent loop and missing a semicolon is a syntactical error.
Missing Database Caching
PHP scripts are mostly used with SQL database which should be handled properly. After using a database it is suggested to have database cache so that it can be recovered in the time of need if some misshapen happens. Memcached is one of the best and free software providing a cache system to a famous website like Facebook. It is recommended to use a cache system before going ahead.
Not Using E_ALL Reporting
The error reporting feature is available in PHP which automatically reports the bug. Need is to turn this feature on and it takes much of guesswork. If bugs are reported then it can speed up the development process and reduce time. E_ALL is one of the strict types of error reporting but most developers don't know about it. Make use of it even when you have to report the smallest error. After development turn it off because a lot of bugs on screen can annoy user for smooth running.
Not Setting Time Limits on PHP Scripts
Scripts run according to the time. The unresponsive script makes programs most crankier and a good programmer knows it well. Program execution failing can be avoided by setting a time limit on scripts like set_time_limit. It’s the best preparation before jumping into the well of bugs which causes headache and hypertension.
Not Validating Cookie Data
People don’t think more about the invalid data passing by a cookie. Not validating cookie data can be harmful and it can open your code for potential harm. To overcome the potential harm situation use some functions like htmlspecialchars() or another one is mysql_real_escapoe_string(). With these functions, cookie data is validated before storing them into a database.
Not Escaping Entities
PHP developers trust data validity and don't bother to check its sparseness. It is harmful to the whole script to store data without checking. Data is validated by some functions like hemlspecialchars() or htmentities(). Whole syntax would be like Echo htmlspecialchars ($_GET[‘username’], ENT_QUOTES);
Confusion about Pass by Reference or Pass By Value
What happens here developer doesn't get an idea when and where values should be returned by reference or by values. PHP return array by value until and unless it is not declared explicitly (by using &). It means that the array copy would be returned. Caller and called function wouldn't be getting the same instance of the array.
Memory Usage Headfakes and Inefficiencies
Fetching or running more than 1 query at once always prove helpful rather than executing a single query at a time. Single query execution can lead the program out of memory situation.
Ignoring Unicode/UTF-8 Issues
These are common errors which appear during debugging but not a suitable approach ever used to solve them. PHP'6 core edition was made which was Unicode sensitive but it failed when the development of PHP 6 was postponed in the backend of the years 2010.
Wrong Comparison Operator
Comparison operators are a basic and fundamental part of PHP programming, using inappropriate operators can breach your program. Most frequently misused operators include =, ==, !=, etc. when speedy programming is being done then chances of occurrence of such bugs become high.