joe-oli

/*
Sure, here is the code for a Windows Service with the Microsoft.Extensions.Hosting.BackgroundService:
*/
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Configuration;
using Microsoft.EntityFrameworkCore;

namespace MyService
{

joe-oli

//Q: explain the meaning of default in
private DispatcherTimer timer = default!;

/*
Bard::
Sure. The default keyword in the code private DispatcherTimer timer = default!; means that the timer variable will be initialized with the default value for a DispatcherTimer object. In this case, the default value is a DispatcherTimer object that is not running and has a Interval of 0 milliseconds.
The default! syntax is a new feature in C# 10 that allows you to explicitly specify that the default value should be used. This is useful for preventing the compiler from inferring the wrong type for the variable. In this case, the compiler could have inferred that the timer variable is a Nullable<DispatcherTimer> object, but the default! syntax prevents this from happening.

Here is a breakdown of the code:
•	private - This keyword specifies that the timer variable is private. This means that it can only be accessed by other members of the class in which it is declared.

joe-oli

/*
Show sample code for MyDbInitializer()

=>
Sure, here is a sample code for MyDbInitializer():
*/
public class MyDbInitializer : DbInitializer
{
    public override void Seed(DbContext context)
    {

joe-oli

/* how to use the CHECK constraint to enforce the data type and length of the AgentCode column in the Agent table: */

CREATE TABLE [dbo].[Agent](
  [AgentID] [int] IDENTITY(1,1) NOT NULL,
  [AgentCode] [char](8) NULL,
  [Invalid] [bit] NULL,
  [ExtSysAgentGuid] [uniqueidentifier] NULL,
  [BusinessName] [nvarchar](200) NULL,
  ...
  CONSTRAINT [CHECK_AgentCode] CHECK ([AgentCode] IS NULL OR [AgentCode] LIKE '____-____')

joe-oli

[
    {
      "name": "Apple",
      "color": "Red",
      "taste": "Sweet"
    },
    {
      "name": "Banana",
      "color": "Yellow",
      "taste": "Sweet"

joe-oli

The command to create and checkout a branch with a single step is:

```
git checkout -b <branch_name>
```

Here's a breakdown of the command:

* `git checkout`: This is the command used for switching branches.
* `-b`: This flag tells `git checkout` to create a new branch if it doesn't already exist, **and** switch to the newly created or existing branch.

joe-oli

var dialog = new FolderBrowserDialog();
dialog.ShowDialog();
folderpathTB.Text = dialog.SelectedPath;
    

joe-oli

#1 Change the DB to single-user mode;
e.g. in SQL Configuration Manager, SQL Server services / <Your Server> / Properties / Startup Parameters
-f (Add, Apply)
RESTART (or stop, start)

#2
C:\Users\Administrator>SQLCMD -H $localhost
1> CREATE LOGIN newSA WITH PASSWORD = 'Pass@123'
2> go
1> ALTER SERVER ROLE sysadmin ADD MEMBER newSA

joe-oli

List ALL branches
>git branch

LIST branches by wildcard
>git branch --list "122160*"

======================
CLONE A SINGLE BRANCH
======================

joe-oli

declare @result int

SET @result = (NEXT VALUE FOR dbo.auto_seq)

select @result