Detailed description of ASP. NET written examination questions

ASP. NET pen questions are basically essential for ASP. NET programmers. Which of the following questions and answers frequently appear? This article collects some common ASP. NET written examination questions for your reference.

1. SQL part of ASP. NET written test questions:

Q: What is the difference between clustered index and non-clustered index:

A: The body content is a directory arranged according to certain rules. It is called "clustered Index ". The ASP. NET Server Directory is purely a directory, and the body is purely a text sorting method called "non-clustered Index"

Q: What is the significance of indexes? A brief description of the Cluster Index and its advantages and disadvantages

A: clustered indexes usually speed up the UPDATE and DELETE operations, because these two operations need to read a large amount of data. It may take a long time to create or modify a clustered index, because the two operations must be performed on the disk to reorganize the rows of the table. However, INSERT slows down. Clustering indexes can be used for columns that contain a limited number of unique values. For example, a state column contains only 50 unique state codes. Use the following operators to return the query of a range value: BETWEEN,>, >=, <, and <=.

Q: What does the isolation level mean? What are the isolation levels?

A: The transaction prepare to accept inconsistent data is called the isolation level. The isolation level is the degree to which a transaction must be isolated from other transactions. Low isolation levels can increase concurrency, but the cost is to reduce data correctness. On the contrary, high isolation levels can ensure data correctness, but may have a negative impact on concurrency. The isolation level required by the application determines the locking behavior used by SQL Server.

SQL-92 defines four isolation levels that SQL Server supports:
◆ The lowest level of uncommitted read transaction isolation, which can only ensure that the data is not read physically damaged ).
◆ Submit the SQL Server read level by default ).
◆ Repeatable read.
◆ The highest level of serializable read transaction isolation, with full isolation between transactions ).

If the transaction runs at the serializable read isolation level, it can ensure that any concurrent overlapping transactions are serialized.

Q: Brief introduction to the transaction

A: The transaction must run at a Repeatable read or higher isolation level to prevent the loss of updates. When two transactions retrieve the same row and then update the row based on the original retrieval value, the update will be lost. If two transactions use an UPDATE statement to UPDATE rows and do not UPDATE the rows based on the previously retrieved values, the UPDATE will not be lost at the default committed read isolation level.

2. ASP. NET Programming Language Part C/C ++/C #)

Q: process and thread

A: Generally, a process is defined as an instance running a program. A process consists of two parts:
ASP. NET Server 1. System Kernel Object Process Control Block)
ASP. NET Server 2. Code, data, and resources required for running a space package, such as heap and stack );
ASP. NET Server ASP. NET Server processes are inactive and only provide one runtime environment.
The ASP. NET Server thread is a running branch of a process. It executes code in the environment provided by the process. A process must have at least one thread. Otherwise, there is no need to exist.
The ASP. NET Server thread package spans one kernel object and one stack. The thread is the CPU scheduling unit.
ASP. NET Server ASP.. NET Server threads are the smallest unit for running processes. Processes participate in resource allocation, such as handles and memory. threads do not participate in resource allocation!

Q: When to perform packing and unpacking

A: When the conversion between the reference type and the Value Type

Q: What is CLR?

A: CLR (Common Language Runtime) is the basis for building the entire. net framework. It is the key to implementing core features such as. Net cross-platform, cross-Language, and code security.

Q: What is the relationship between. Net and COM?

A :. net supports COM and.. Net components can be implemented through Runtime Callable Wrapper (RCW.. Net, and use COM Callable WrapperCCW) to obtain the COM component.. Net component.

Q: What is the intermediate language (IL) in. Net?

A :. the intermediate language in. Net can be defined in the runtime specification of a common language ,. A collection of commands that are independent of the CPU and are converted to local code through the Just In Time compiler during execution. It is a core part of language interoperability on the. Net platform. All. Net platform languages must be compiled into intermediate languages (IL) first ).

3. ASP. NET test questions-WEB development

Q: What is written in the ASP file header that will force the web server to check the variables used in any program to be defined first?

Answer: Option explicit

Q: If you do not want an error to affect the execution of the entire ASP page, what can you do in the header?

A: On error resume next

Q: I hope that the ASP page will not be cached, that is, it will be automatically refreshed every execution. What can I do if I write a sentence?

Answer: Response. Expires =-1
ASP. NET Server Response. ExpiresAbsolute = Now ()-1
ASP. NET Server Response. cachecontrol = "no-cache"

1. Analysis of ASP. NET pen questions
2. Simple Q & A for ASP. NET pen questions
3. Miscellaneous on the learning path of ASP. NET programmers
4. Development Analysis of ASP. NET Custom Controls
5. Summary of ASP. NET pen questions