Entity Framework筆記(二)_Database First使用方式

- 2月 24, 2022

EntityFramework 主要提供的Workflows有如下幾種

1. Database First

2. Model First

3. Code First

所謂DB First也就是EF跟既有的資料庫連接後對應資料表去生成相應Model Class

而這些Model類別會再去衍生出相應Entities跟Context的類別

在Model這一層事實上是Read-Only的任何異動都必須從DB來去下手

這裡準備好一個.net framework 的 ConsoleApp專案

並且準備好你的DB和相應Table

USE [Master];
GO
CREATE DATABASE DatabaseFirstTestDB ON ( NAME = DBFirstData, 
                    /* Point to the directory wherer you want to store your db files */
                    FILENAME = 'E:\IT_Db\DBFirstTest.mdf',
                    SIZE = 10MB,
                    MAXSIZE = 50MB,
                    FILEGROWTH = 5MB )
                    LOG ON ( NAME = DBFirstLog,
                    /* Point to the directory wherer you want to store your db files */ 
                    FILENAME = 'E:\IT_Db\DBFirstLog.ldf',
                    SIZE = 5MB,
                    MAXSIZE = 25MB,
                    FILEGROWTH = 5MB);
GO
USE [DatabaseFirstTestDB];
GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Contact](
    [Id] [int] NOT NULL PRIMARY KEY,
    [Name] [nchar](30) NULL,
    [Nickname] [nchar](30) NULL,
    [Age] [numeric](18, 0) NULL
) ON [PRIMARY]
GO
CREATE TABLE [dbo].[ContactAddress](
    [Id] [int] NOT NULL PRIMARY KEY,
    [ContactId] [int] FOREIGN KEY References Contact(Id),
    [AddressLine1] [nchar](20) NULL,
    [AddressLine2] [nchar](20) NULL,
    [City] [nchar](20) NULL,
    [StateProvince] [nchar](10) NULL,
    [PostalCode] [nchar](10) NULL
) ON [PRIMARY]
GO
CREATE TABLE [dbo].[ContactEmail](
    [Id] [int] NOT NULL PRIMARY KEY,
    [ContactId] [int] FOREIGN KEY References Contact(Id),
    [Email] [nvarchar](100) NULL
) ON [PRIMARY]
GO