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Initialisation of a new Vue project

Initialisation of a new Vue project is easiest done with yarn (you can also use npm).

First we need to inicialize the project via:


yarn init

Then we can start adding packages. Vue would be first package:

yarn add vue

Recent posts

Useful GIT commands

I will collect here useful GIT commands, that come handy in every day developer's life.

Local repository initialisation from remote one:git clone https://repo.git Get new remote repository data:git pullGet current status of the local repository:git status

Entity Framework Exception - A referential integrity constraint violation occurred

Entity Framework Exception - A referential integrity constraint violation occurred. When you get this type of the exception it just simply means that you need to match Ids of the related entities.

Exception: A referential integrity constraint violation occurred: The property value(s) of 'Image.Id' on one end of a relationship do not match the property value(s) of 'BaseEntity.SomeImageId' on the other end. 

A typical mistake that cause this exception is:

baseEntity.SomeImageId (type of Image)

and

Image.Id

Does not match.

So if you change the new added related entity to the negative Ids (see the related blog post), then you also need to modify the parent end of the Id (one end of the relationship as Entity Framework expression goes). So that both "ends" have the same Id value.

Entity Framework exception - adding new Detached Object to the DbContext

Entity Framework exception - adding new Detached Object to the DbContext? How to?

When you see this exception:

Exception: Attaching an entity of type 'Image' failed because another entity of the same type already has the same primary key value. This can happen when using the 'Attach' method or setting the state of an entity to 'Unchanged' or 'Modified' if any entities in the graph have conflicting key values. This may be because some entities are new and have not yet received database-generated key values. In this case use the 'Add' method or the 'Added' entity state to track the graph and then set the state of non-new entities to 'Unchanged' or 'Modified' as appropriate.

This just mean that you need to properly handle detanched entities Ids. This exception means that two of your newly added entities have the same Id. Typically the value of the Id is 0.

So the solution is that you need to manually change Ids. You need to …

How to create new MS SQL virtual machine in Azure

How to create MS SQL virtual machine in Azure and how to enable MS SQL Login user.

1. Create new virtual machine with MS SQL server
2. Open a MS SQL port 1433 in azure management for the given virtual machine
3. Log in to the virtual machine
4. Open port in firewall in virtual machine Windows system - 1433
5. IMPORTANT - Set MS SQL setting to the Mixed Mode (Windows Authentication and SQL Server Authentication) (default is only Windows Auth.)