Entity Framework Core + Oracle (edit)

1. Update Model from Database...
2. Generate Database from Model...

Entity Framework, LINQ and Model-First for the Oracle Database

https://www.oracle.com/webfolder/technetwork/tutorials/obe/db/dotnet/EntityFrameworkOBE/EntityFrameworkOBE.htm

Entity Framework Core tools reference - .NET Core CLI

https://docs.microsoft.com/en-us/ef/core/cli/dotnet

dotConnect for Oracle

https://www.devart.com/dotconnect/oracle/articles/efcore-database-first-net-core.html

Starting with an existing database

https://www.learnentityframeworkcore.com/walkthroughs/existing-database

Oracle DB First

https://www.devart.com/dotconnect/oracle/articles/efcore-database-first-net-core-entity-developer.html

Oracle Command - Inserting Data in Run Time

https://www.devart.com/dotconnect/oracle/articles/tutorial-command.html

To insert the first row into table dept you can use the following statement:

1. CREATE TABLE dept:

   CREATE TABLE dept (
     deptno INT PRIMARY KEY,
     dname VARCHAR(14),
     loc VARCHAR(13)
   )
   

2. CREATE TABLE emp:

   CREATE TABLE emp (
     empno INT PRIMARY KEY,
     ename VARCHAR(10),
     job VARCHAR(9),
     mgr INT,
     hiredate DATE,
     sal FLOAT,
     comm FLOAT,
     deptno INT REFERENCES dept
   )

INSERT INTO dept (deptno, dname, loc) VALUES (10,'Accounting','New York')

The following code fragment executes the query:

OracleConnection conn = new OracleConnection("User Id=scott;Password=tiger;Server=OraServer;");
OracleCommand cmd = new OracleCommand();
cmd.CommandText = "INSERT INTO dept (deptno, dname, loc) VALUES (10,'Accounting','New York')";
cmd.Connection = conn;
conn.Open();
try {
  int aff = cmd.ExecuteNonQuery();
  MessageBox.Show(aff + " rows were affected.");
}
catch {
  MessageBox.Show("Error encountered during INSERT operation.");
}
finally {
  conn.Close();
}

Console Application - How You Can Create a .NET Core Application Using Entity Framework Core with Oracle

https://www.talkingdotnet.com/create-net-core-application-using-entity-framework-core-with-oracle/

1. Update Model From Database...
2. Update Database from Model...
3. Generate Database Script From Model...

ASP.NET Core Web API with Entity Framework Core (edit)

CRUD Operation in ASP.NET Core Web API with Entity Framework Core

https://www.codeproject.com/Articles/1259484/CRUD-Operation-in-ASP-NET-Core-Web-API-with-Entity

https://github.com/mukeshkumartech/CRUD-AspNetCore-WebAPI

ASP.NET Core 2.1 - Implement Entity Framework Core In A Code First Approach

https://www.c-sharpcorner.com/article/entity-framework-core-a-code-first-approach/

ASP.NET Core Web API with EF Core DB-First Approach

https://code-maze.com/asp-net-core-web-api-with-ef-core-db-first-approach/

https://github.com/CodeMazeBlog/ef-db-first

How To Quickly Create A New Database Using EntityFramework Core On ASP.Net Core

CompatibilityVersion.Version_2_1

http://bekenty.com/entityframework-core-asp-net-core/

https://github.com/BekenJB/EmployeeManagerWithEFCore

Xóa bản ghi trùng lặp trong SQL Server Table

WITH student_cte AS (
    SELECT 
        First_Name, 
		Last_Name,
		Phone, 
        ROW_NUMBER() OVER(
            PARTITION BY 
                First_Name, 
                Last_Name, 
                Phone
            ORDER BY 
                First_Name, 
                Last_Name, 
                Phone
        ) rn
     FROM dbo.Students
)
select * from student_cte;

WITH student_cte AS (
    SELECT 
        First_Name, 
		Last_Name,
		Phone, 
        ROW_NUMBER() OVER(
            PARTITION BY 
                First_Name, 
                Last_Name, 
                Phone
            ORDER BY 
                First_Name, 
                Last_Name, 
                Phone
        ) rn
     FROM dbo.Students
)
DELETE FROM student_cte WHERE rn >1;