The reason for this exception may be that the corresponding assembly is not introduced into the project. Generally speaking, the problem is solved after the required assembly is introduced. Sometimes there is a strange problem. For example, project B is a class library. Project a refers to the class of project B, such as userservice. Project B is also introduced into the reference of project A. However, when compiling in project a, an error is reported, saying that the type or namespace name ‘userservice’ does not exist in the namespace ‘xxx’ (are you missing an assembly reference?)

Now, for example, is there anything related to warning

The referenced assembly ” XXX.Service.dll ” could not be resolved because it has a dependency on ” System.ServiceModel.Web , Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″ which is not in the currently targeted framework “.NETFramework,Version=v4.0, Profile=Client”. Please remove references to assemblies not in the targeted framework or consider retargeting your project.

That is to say, because the Framework version used by project a and project B is different, the class of a cannot be used in project B. At this point, as long as the Framework version of the project is reset to make the two projects consistent, the problem is solved.

string sql = "INSERT INTO TempTable (A, B, C) VALUES ('2222222', '1111111', 'RRR')";
OracleCommand cmd = new OracleCommand(sql, connection);
cmd.ExecuteNonQuery();

When executing this code, the first insertion failed. When stop debug restarts, it is found that the program runs to cmd.ExecuteNonQuery It’s stuck when I’m in. The reason for this is Oracle’s block mechanism.

If session “A” inserts a row in a table with a primary key, session “A” will block ANY other session attempting to insert the same primary key until session “A” commits or rolls back the insert. All other attempts to insert will “hang”.

At this point, I change the primary key 2222222 of SQL statement into 33333333 in the code, and then I can insert it smoothly. This indicates that this operation will be blocked only when the primary key is the same. Because when 2222222 was inserted, the program ended unexpectedly, but the Oracle transaction was not committed or rolled back, so this primary key was locked. Note that it’s just the primary key of this value.

there is another problem here, that is, when I open SQL developer and execute the primary key statement of 2222222, the execution will be completed smoothly without blocking. Now, when I execute SQL statements with code, the blocking phenomenon will still occur. But when I restart vs, create a new project and write these codes, it is also equivalent to another program to execute the insert statement, which will also get stuck. May be related to the. Net provider used?Because you are using the same provider, it is stuck. Because SQL developer doesn’t use this provider, it won’t get stuck?It’s just a guess.

This kind of lock is called tmlock, or row transaction lock. You can use SQL statements to check whether there is such a lock
or not

SELECT sid, id1 FROM v$lock WHERE TYPE=’TM’

SID ID1
76 14197

SELECT * FROM dba_ objects WHERE object_ id = 14197;

OBJECT_ NAME
——————————————————————————————————————————–
TemTable

How to release this TM lock?row transaction lock

Just execute a commit command in the SQL developer UI.

In deployment ASP.NET When the website is deployed to IIS, visit the page http://localhost/UserCenter/user.aspx , but an exception was thrown. At this time, to detect whether the deployment is successful, you can write a text file for testing in the root directory text.txt , and then access the file http://localhost/UserCenter/test.txt If you can see the contents of this file, it means that there is no problem with the deployment. Maybe there is a problem with the code.

Abnormal prompt:

HTTP error 404.3 – not found
the page you are asking cannot be served because of the extension configuration. If the page is a script, add a handler. If the file should be downloaded, add a mime map.

abnormal screenshot

The reason for this problem is that there are multiple. Net versions on the machine, so there are multiple ASP.NET Version. Now our application pool is in version 4.0, but this version is not registered in IIS, so this error is reported. Now what we need to do is register the 4.0 ASP.NET Version. In C: windows\ Microsoft.NET \Find IIS registration tools, namely aspnet, in the directory of framework64/v4.0.xxxx_ regiis.exe Then start it in the form of a DOS window, aspnet_ Regiis – I refer to MSDN for details http://msdn.microsoft.com/en-us/library/k6h9cz8h%28VS.80%29.aspx

Running results

At this point, restart the application pool and website, and you can see the normal ASPX rendered page.