Question

我现在正在尝试使用EF Core，并决定尝试将SQLite作为提供商。我在互联网上遵循了一些指示，并从stackoverflow的Feed中考虑了this topic。不知怎的，我不会创建我的多个表。

这就是我的DbContext文件的样子：

$ dotnet ef database update
Project ConsoleApp.SQLiteVS (.NETCoreApp,Version=v1.1) was previously compiled. Skipping compilation.
Executed DbCommand (4ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
Executed DbCommand (35ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE TABLE "__EFMigrationsHistory" (
    "MigrationId" TEXT NOT NULL CONSTRAINT "PK___EFMigrationsHistory" PRIMARY KEY,
    "ProductVersion" TEXT NOT NULL
);
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
Executed DbCommand (2ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
SELECT COUNT(*) FROM "sqlite_master" WHERE "name" = '__EFMigrationsHistory' AND "type" = 'table';
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
SELECT "MigrationId", "ProductVersion"
FROM "__EFMigrationsHistory"
ORDER BY "MigrationId";
Applying migration '20170117155520_MyFirstMigration'.
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
Executed DbCommand (3ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE TABLE "Blogs" (
    "BlogId" INTEGER NOT NULL CONSTRAINT "PK_Blogs" PRIMARY KEY AUTOINCREMENT,
    "Url" TEXT
);
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE TABLE "Groups" (
    "Id" INTEGER NOT NULL CONSTRAINT "PK_Groups" PRIMARY KEY AUTOINCREMENT
);
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE TABLE "Users" (
    "Id" INTEGER NOT NULL CONSTRAINT "PK_Users" PRIMARY KEY AUTOINCREMENT
);
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE TABLE "Posts" (
    "PostId" INTEGER NOT NULL CONSTRAINT "PK_Posts" PRIMARY KEY AUTOINCREMENT,
    "BlogId" INTEGER NOT NULL,
    "Content" TEXT,
    "MadeBy" INTEGER NOT NULL,
    "Title" TEXT,
    CONSTRAINT "FK_Posts_Blogs_BlogId" FOREIGN KEY ("BlogId") REFERENCES "Blogs" ("BlogId") ON DELETE CASCADE
);
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE TABLE "UserGroup" (
    "UserId" INTEGER NOT NULL,
    "GroupId" INTEGER NOT NULL,
    CONSTRAINT "PK_UserGroup" PRIMARY KEY ("UserId", "GroupId"),
    CONSTRAINT "FK_UserGroup_Groups_GroupId" FOREIGN KEY ("GroupId") REFERENCES "Groups" ("Id") ON DELETE CASCADE,
    CONSTRAINT "FK_UserGroup_Users_UserId" FOREIGN KEY ("UserId") REFERENCES "Users" ("Id") ON DELETE CASCADE
);
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE INDEX "IX_Posts_BlogId" ON "Posts" ("BlogId");
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
CREATE INDEX "IX_UserGroup_GroupId" ON "UserGroup" ("GroupId");
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
INSERT INTO "__EFMigrationsHistory" ("MigrationId", "ProductVersion")
VALUES ('20170117155520_MyFirstMigration', '1.1.0-rtm-22752');
Done.

由于某种原因，当我开始初始迁移时，它没有生成表Users，Groups。这是迁移过程中的日志：

Remove-ItemProperty

正如您所看到的，这些表似乎已经创建了，但是当我使用Firefox＆＃39; es DB Manager打开db文件时，我只能看到创建的帖子和博客表。

我该如何解决？

Answer 1

目前，您必须自己创建“多对多”表：https://docs.microsoft.com/en-us/ef/core/modeling/relationships#many-to-many

这是未来版本的路线图：https://github.com/aspnet/EntityFramework/wiki/Roadmap

无法与EF Core的SQLite提供程序创建多对多关系

1 个答案: