jpa interview questions

Common Database interview questions and database questions Paradigm 1: Each column in a database table is a basic data item that cannot be further divided. values or duplicate attributes are not allowed. For example, if a table contains a phone number field, the value has a mobile phone number, there is another seat number, which does not match.Summary: fields c

Js interview questions-inheritance of js, js questions-js Js is a flexible language. There are often multiple ways to implement a function. ECMAScript does not have a clear Inheritance Mechanism, but is achieved through imitation. According to the characteristics of js, js implementation inheritance has the following common methods:1. Use object impersonating to

10 classic Java interview questions and classic java questions 1. How does Java's HashMap work? HashMap is a key value for the data structure. Each key has a corresponding value. The key is to identify such a value. Based on the hashing principle, HashMap stores and obtains objects through put () and get () methods. When we pass a key-value pair to the put () m

Computer Network interview questions, computer network questions 1,OSI Layer-7 protocol,Layer-4 TCP/IP protocol,Five-Layer Protocol mentioned in instructor Xie xiiren's online textbookComparison Note: (1) OSI's layer-7 protocol is only a theoretical protocol, which is not actually used. (2) the architecture of the layer-4 TCP/IP protocol in practice. (3) The fiv

Ddchuxing -- Summary of php interview questions and ddchuxingphp questions 1. Differences between echo and print Echo has no return value. print has return value 1. If the execution fails, false is returned. echo outputs faster than print because no return value exists. echo can output one or more strings, print can only output one string. print can be used for c

PHP interview questions, php questions Tip: Set the PHP file character encoding header ("content-type: text/html; charset = UTF-8") before the test code "); 1. 1.1 Use PHP to get the current time and print it. Format: 22:19:30 2. 2.1 convert string to array $ Str = "www.baidu.com ";$ Arr_str =Explode('.', $ Str );Print_r ($ arr_str); // Array ([0] => www [1] =>

Java interview questions, java questions 1. storage structures used by stacks and queues Chain storage and sequential Storage 2. understanding of time complexity and space complexityTime Complexity: Number of statement executions in an algorithm, which is T (n). When n changes, it is O (f (n). For example, constant O (1 ), O (n2), O (nlog2n)Space complexity: t

This article focuses on the question of Ajax questions and answers, you can take a look at the interview of those who are how to issue, and see what the correct answer is. Now, let's see this article. 1. Do you interact with the background during work? Well, can you tell me a few parameters in the encapsulated Ajax? URL: The address where the request was sent. Type: The request method (post or get) defaults

according to your design to complete the following scenarios. 1. Find five articles closest to the specified article (similarity algorithms are based on the number of identical labels, and the larger the number, the more similar) Integrated Knowledge Section: 1. Talk about your understanding of cookies and sessions, what their application scenarios are, and how they might be able to explain how the session can be shared under a variety of applications. 2. Talk about your understanding of single

During the interview, you are usually asked to fill in two tables. One is your detailed information table, and the other is the answer to the questions.Both of them should pay attention to whether there are content in the anti-positive aspect. If you test your server, there are usually two types, that is Program Connect to the database or some basic Algorithm (Binary Search, recursion, etc.), the company generally tests whether your basic skills are s

Common Database interview questions and database questions1. Foreign key candidates for primary key superkeys Primary key: A combination of data columns or attributes that are unique and fully identified for the stored data objects in the database table.A data column can have only one primary key.And the value of the primary key cannot be missing, that is, it cannot be Null ). Superkeys: The attribute set t

Activity interview questions, activity questionsWhat is Activity? Activity is one of the four main components of Android. Generally, a user interface corresponds to an Activity. At the same time, Activity is a subclass of Context, and it also implements the Window interface and KeyEvent interface to process the Window-User Interaction Events.Briefly describe the lifecycle of the Activity Activity lifecycle

Select an appropriate function declaration for the user-defined function is_leap. Is_leap uses 2000 as the default year. Php programmer recruitment questions: Problem 1. select the appropriate answer and fill in the blank space PHP is a ______ scripting language based on the ______ engine. PHP is most often used to develop dynamic ______ In addition, it can also be used to generate ______ (and others) documents. A. dynamic, PHP, database, HTML B. embe

Java interview questions, java questions1/** 2 * write a function. It accepts an integer (assuming length) and returns an array. The length of the array is length, 3 * the content in the array is a random value ranging from 0 to (length-1) and cannot be repeated. 4*5 * If the length is 5, the array may be [, 4]. 6*7 * @ author Administrator 8*9 */10 11 import java. util. arrayList; 12 import java. util. lis

8 PHP array interview questions and php array questions I have prepared to record the PHP array questions on the Internet. 1. Write a function to create an array with a length of 10. The elements in the array are an increasing odd number and the first item is 1.Copy codeThe Code is as follows: Function arrsort ($ first

Share several typical javascript interview questions and several javascript questions These questions are a bit interesting. You can study them to help you improve your skills. 1. What is output during the call process? Function fun (n, o) {console. log (o); return {fun: function (m) {return fun (m, n) ;}} var a = f

Sizeof series pen questions seem simple. In fact, if you don't go into depth, it is easy to make mistakes, and I am sometimes defeated here. I will give a conclusion in my close-up blog, taking it as a warning.Differences between V1.0 32-bit and 64-bit Compilers The test code is as follows: # Include "stdafx. H "# include The execution result is as follows:V2.0 sizeof character array The test code is as follows: # Include "stdafx. H "# include The e

Java learning path-simple basic interview questions, java path-Questions 1. What are the features of object orientation? A: The object-oriented features mainly include the following: 1) Abstraction: Abstraction refers to the process of summarizing the common features of a class of objects to construct classes, including data abstraction and Behavior Abstraction.

Summary of interview questions and summary of questions 1. Describe the animation mechanism in detail2. Describe the event mechanism3. Description: Measure and Layout. Draw process. When the size of a subclass changesWhat kind of chain reaction will it cause?4. What are the four main components of Android? 4 startup modes of Activity5. Start the Service in two w

[Programmer interview questions selected 100 questions] 11. Search for binary tree images.[Question] Enter a binary search tree and convert it to its image. That is, in the converted Binary Search Tree, the nodes in the left subtree are greater than those in the right subtree. Use recursive and cyclic methods to convert tree images. For example, enter: 8/\6 10/\/