Jack Ramon

All of them are good certification you can choose any one of them, Certification is justifying a way for professionals like IT employees to validate their knowledge and obtain credibility that will lead a candidate to better opportunities.

Modern Java EE is heading to the cloud. Servlets still remain relevant but JSPs not so much. Instead there are modern web-framework apps in pure HTML5/CSS/JS served to the client as static content.

Java EE 8 introduces major and minor updates to core APIs such as Servlet 4.0 and Context and Dependency Injection 2.0. It also introduces two new APIs—Java API for JSON Binding (JSR 367) and the Java EE Security API (JSR 375).

John Haugeland’s Artificial Intelligence - the Very Idea is a classic. Gives insight on the problems that early AI innovators faced when trying to map cognition into computation.
Superintelligence by Nick Bostrom talks about the possibility of AI being smarter than us. There’s also a series of machine learning e-books by Dr. Jason Brownlee, Products - Machine Learning Mastery that give you lots of practical knowledge.

Preparation time for Java Certification vary from person to person and it requires lot of dedication & hard-work.

Both the exam each takes around 2 months of time if you have little background on Java already. It also depends on how you are preparing for the exam. OCPJP is more tougher than OCAJP Exam. OCAJP can be cleared with out much in depth knowledge on Java programming but OCPJP covers lot of topics that requires some kind of practice.

Static variable: When you need something that will be used through out the application and every instance need to know the variable.

Instance variable: It will be different from object to object and object's property while static variable is Class's property.

Static function: Used to do some utility task. Can be called without any object declaration.

Instance function: Need object to call this function.

static or instance depends on your uses .

If I understand your question correctly I think this is what you are looking for?

<?php echo $GLOBALS['wp_query']->request; ?>
$wp_query is a global variable that contains the current query run by the loop. If you run the above code anytime while the loop is still active or even right after the loop it should give you the SQL from the loop. Just make sure you inspect it before letting something else run that uses query_posts() again.