Weather used in php or any other scripting language… sometimes we have the need to query a database in order to fetch or manipulate certain data.
One of the most common request, widely written and used is
SELECT * FROM MyTable WHERE ID=’ValueX’ and NAME=’ValueY’;
now, ID and NAME are just columns… so nothing special
However.. how could someone optimize that line of code? Fact is, lots of coders out there, do not realize how unoptimize this line could be and the different problems it could generate.
So how do I optimize this line… although not much syntax will be needed to change
1) Put INDEXES key on both ID and NAME (or whatever are your column)…
2) Find which combination will return less values and use that combination as the first condition…
That’s it 
1. if you were to use between print or echo… use echo (Echo is known to be faster than print)
2. when doing string searches or action, do not simply/quickly jump on regex, but first have a look at php api’s string functions such as strpbrk, stripos etc..
3. Display smart error messages… A lot of young developers like to display a custom error or show systems errors whenever something break. Although it is good practice to alert the user of any error, keep in mind printing Error cost a lot in resources. Go for general error display then specifics.
4. Close your database connections when you are done processing mysql datas
5. Use variables instead of global variables
6. Always initialize your variables… It seems too common for coders to just declare a variable without initializing it and process it later with increments etc… Remember you are loosing on speed with none initialized variables
7. Whenever you echo a string on the string.. use ‘ ‘ instead of ” “… why? because PHP will look inside the ” ” declaration for any variables “$”… the process is therefore slower
8. Use mem-cached with apache as to cache memory objects. This will highly speed up the runtime execution of your web application
9. Use mod_gzip to compress data delivery
10. Implement data structure as array and not as class
and yes… use less OOP as possible, being a JAVA and .NET programmer, I can guarantee that OOP in PHP is just a big overhead.
till later,