Restriction: polynomial time decision of instance is why needed to “decision Problem”?

I am reading book “combinatorial optimization 3rd edition(Bernhard Korte、 Jens Vygen)”.

(latest version is sixth.)

There are some discriptions in this book that I don’t understand

Not all binary strings are instances of Hamiltonian Circuit but only those representing an undirected graph. For most interesting decision problems the in- stances are a proper subset of the 0-1-strings. We require that we can decide in polynomial time whether an arbitrary string is an instance or not:

  • quote from p350

decision problem is pair P = (X,Y), where X is a language decidable in polynomial time.

  • quote p351

Why decision problem required that decide in polynomial time whether an arbitrary string is an instance or not?

I can’t found any reasons of this restriction in the book.

SQL Database ‘Project_Content’ on SQL Server instance ‘XXX’ not found – after removing project server

I keep getting this error in event viewer. I reckon project server was installed before on the farm and it has been removed but it seems its still looking for the content database see error below

SQL Database 'Project_Content' on SQL Server instance 'XXX' not found.  Additional error information from SQL Server is included below.  Cannot open database "Project_Content" requested by the login. The login failed. Login failed for user XXX\'. 

How can i stop this and where can i inform the SP farm that it doesn’t exist anymore. Thanks in Advance

Restoring the Existing Sharepoint farm using different SQL server instance

How to change the Database server instance of the the existing sharepoint 2013, when its current SQL server database instance is corrupt?


->Sharepoint 2013 server lost all the connections to the SQL server database due to server failure (server farm is setup on virtual machine and SQL server on different Virtual machine)

we were able to retrieve the sharepoint databases(including config and content dbs) which were month old.

we have attached these database to the new SQL server instance created (this time the database instance name is different)

but we are not able to configure the existing SharePoint 2013 server to the new database SQL server instance

we tried running the configuration wizard, and also change the server setting running the cliconfg.exe (C:\windows\system32)

but it still points to the old server instance. can anyone please suggest how to restore these sharepoint sites without re-installing the sharepoint 2013 server

thanks n regards

WebDAV issues since moving SQL instance

We are currently running a SharePoint 2013 farm on-site, and one of our intranet sites is used for file storage & collaboration. For one specific business case, users use a mapped drive to quickly upload files to a given location. The process has worked well for the past few years with no issues.

A month ago we moved our databases to a new SQL instance. We are using aliases for everything, so it was pretty much just a question of updating the alias on each SharePoint server. Everything seems to have gone smoothly, but now I’m detecting what may be a problem.

Out of 400 or so users, I’ve had four users report that they can no longer upload files via WebDAV. Small files seem to work ok, but anything larger than 450-500MB returns the error “Can’t read from the source file or disk.” The problem is intermittent even with these users, and therefore difficult to troubleshoot. The new SQL instance has plenty of room, the content database is large but hasn’t hit any size limits, and manually increasing the WebDAV file size limit in the registry (say, to 1024MB) doesn’t resolve the issue.

In case it’s relevant, we moved from MS SQL 2008 to MS SQL 2017.

Has anyone here encountered this sort of issue before?

Note: Yes, I know using WebDAV and/or storing 400+MB files in SharePoint isn’t ideal, but for the purpose of this question that’s irrelevant. We’ve been using this system for long enough that I know it worked and was stable before the SQL move.

Copy SQL Server DB into another instance without SA access

I’ve two SQL Server databases and both of them are on cloud.

  1. First server is source
  2. Second server is destination

I only have a non SA access. And I’m using DBForge Studio for managing the database. I’m trying to copy the database from the first server to the second server through DBForge→Database Sync→Copy Database and then select copy (I’m following this article).

Note: The database already exists in destination with same name, but no tables yet.

I got an error message when trying to copy:

The EXECUTE permission was denied on the object ‘xp_fileexist’…..

Then I try to copy & overide but I got the same error message.

So I try to use another way like export & import. I export the database from source server into .sql, but there are only queries for insert, it didn’t serve the query for create table schema, and I tried to import into another file like .csv and .xsl but I got the same, it only contain data without schema.

Is there any better way to copy the database without SA access?

New SharePoint 2019 Instance Site Template

We are spinning up a new 2019 SharePoint on prem instance with the intention of migrating our 2013 data to it. Our 2013 main stie has a site template of SPS#0 (SharePoint Portal Server) which is now obsolete. All of our subsites were created using STS#0 (Team Sites). Any recommendations for our 2019 main site template? We’ll be creating all the new subsites with the Team Sites template, should we just use that?

NullReferenceException in SPRequest: Object reference not set to an instance of an object

I have a custom SharePoint timer job definition for SharePoint 2010. In this timer job definition, I am creating the SPSite object (inside the using statement) and then iterating through every sub site using below loop.

foreach (SPWeb web in rootWeb.Webs){}

In side the loop, I am adding multiple items to a custom list. Randomly, item creation is failing with below errors in hive logs.

NullReferenceException in SPRequest: Object reference not set to an instance of an object. at Microsoft.SharePoint.Library.SPRequest.SetVar(String bstrUrl, String bstrName, String bstrValue)

NullReferenceException in SPRequest: Object reference not set to an instance of an object. at Microsoft.SharePoint.Library.SPRequest.ClearAllVars(String bstrUrl)

For every such Null Reference Exception for OWSTIMER.EXE, one or more below w3wp.exe exceptions are coming and I am not sure what is causing this but it seems like it is effecting my timer job code. Is it a good practice to create items in a loop like I have described above?

An SPRequest object was not disposed before the end of this thread. To avoid wasting system resources, dispose of this object or its parent (such as an SPSite or SPWeb) as soon as you are done using it. This object will now be disposed. Allocation Id: {6F311C83-F607-4B16-9173-67858B4CDB70} To determine where this object was allocated, set Microsoft.SharePoint.Administration.SPWebService.ContentService.CollectSPRequestAllocationCallStacks = true.


How Ubuntu 16 instance under AWS upgrade to 18.04 ?

I have Ubuntu 16 instance under AWS
and on login to its console I see message:

New release '18.04.2 LTS' available. Run 'do-release-upgrade' to upgrade to it. 
Code (markup):

I tried to run it following messages in commands :

Last login: Fri Sep 6 06:39:22 2019 from ubuntu@ip-NN-NNN-NN-NNN:~$   clear ubuntu@ip-NN-NNN-NN-NNN:~$   sudo apt-get update Hit:1 xenial InRelease Hit:2...
Code (markup):

How Ubuntu 16 instance under AWS upgrade to 18.04 ?

It seems Xubuntu does ´touch´ a microsd card in a way that is recognizable by retropie for instance – what does it do?

if i for instance insert one of my Retropie microsd cards in my other desktop pc which runs Xubuntu 18.04 LTS, if i do not lock the microsd card with the switch in the SDHC-microsd card adaptor, Xubuntu ´seems´ to do something to the card, in a way that when i put it back in my Raspberry Pi, the Raspberry starts searching folders and other stuff before the initial boot of emulation station. This is a significant symptom i get when i have inserted any microsd card in an other pc or device, when it was not set to be Read-Only. I run Linux Xubuntu 18.04 LTS on all my systems btw. But what does it do with a microsd card which is not Read-Only, and i did not do ANY fileoperation (copying/ deleting whatever) on this card, I only made an Disk (.IMG) with Disks of it. Can anyone tell me what Xubuntu ´does´ to a microsd card inserted in this way. ? It does not corrupt anything but i should assume if i do nothing like copying to it, or deleting from it, there should be ZERO traceable actions of this microsdcard having been inserted in an other computer … ?