Interview question: 1-day Java face question!=!= not seen

1, self-introduction, I directly said the project experience, (which year in which company to stay)

2, asked if there has been a team experience, I said last year.

Is 3,struts a singleton or multi-instance mode? I first say the singleton mode, after saying multiple cases mode.

4,jsp and struts The difference is what, I said a lot of, the interviewer let me not macro said, to refine the said, I give a simple said struts under the filter, interceptors, JSP has El expression and so on.

5, ask me Modeldriven is a class or an interface? I said first is the class, and later changed to say is an interface.

6, what'smodeldriven ? I said it was to return the entity class. Also asked to return such as the user object's properties and directly define the user attribute is different? I do not have, in fact, there is a difference.

What is 7,prepare? I didn't answer it.

8, then asked what complex business encountered in the project, and finally how to solve it? To give an example, I said that the health file project in the large table into a number of small tables, the field into the large JSON, to the background to parse out the small JSON to modify the table data, respectively.
9, Next Test Database knowledge: Title: Age

	name
28	Zhangsan
28	Lishi
30	Wangwu
40	Zhaoliu

Question: How many people in the 28-year-old, several 30-year-olds, 40-year-olds?

I'm going to start with case and then.

Select Age,sum (case age =20 then 1 else 0) as T1,

sum (case age = 1 and else 0) as T2,

sum (case age = Max then 1 Esle 0) as T3

From user

Group BY age; --The sum of this is written half to forget to write a parenthesis.

The interviewer said that if the age of 1-100, then my judgment 100 times, I also said that the statement data is large on the query is very slow.

I changed the sentence again:

Select Age, COUNT (*) from

User

Group by user;

At that time the mood is not good, the attention is not concentrated, to forget writes The age, anyway is very chaotic.

10, finally asked me salary treatment is how much, I said export 5k, later changed to 4k, interviewer said so not confident?

11 Finally the interview tube gave me his 163 mailbox, let me send a piece of code to him. So this interview is over.

Interview question: 1-day Java face question!=!= not seen