code first migrations

1, VS, Package Manager console2, implementation,enable-migrationsError:Migrations has already been enabled in project ' DD '. To overwrite the existing migrations configuration with use The-force parameter.3, implementation,enable-migrations -forceError:The Migrations configuration type ' DD. Configuration ' is not being found in the assembly ' DD '.Reason:When e

EF architecture ~ Migrations and efmigrations in the CodeFirst production environment Back to directory Migrations refers to migration. It is the product of the code first mode of EF. It means that the code changes are reflected in the database, which has two environments, the first is the local development environment

It's been a long time since we've created the model using code first. It's been a bit of a review today, but there are problems.Now wrap it up.After I have done the initial operations, when I update the database with Update-database-verbose, there is always a System.InvalidOperationException: an issue with an instance failureis very annoyed, the Internet to find a lot of solutions always not. But I think it's a problem with my connection string.The co

Clean: Deletes all created database objects, including users, tables, views, and so on. Migrate: Applies the version change to the database in turn. Info: Gets the status of the current database. Those migrations were completed, those migrations to be completed. Execution time and results for all migrations. Validate: Verify the similarities and differen

Label: Style Color Io OS ar use SP file data Before January 1.6, Django only supported adding new models to the database, but could not edit or modify existing models. At that time, the missing functions of Django could be implemented through south. According to the official documentation, PostgreSQL databases are the best supported, followed by MySQL. Currently, SQLite cannot implement the complete migration function.1. New commands Django 1.7 brings us three new commands: Migrate: used to

Database migrations is one of the most powerful features of Laravel. Database migration can be understood as the version controller of the database. The Database/migrations directory contains two migration files, one to create a user table and one for user password resets. In the migration file, the up method is used to create the data table, and the down method is used for rollback, that is, to delete th

Laravel 5.4 solves the error caused by too long special fields in migrations. laravelmigrations Preface This article mainly introduces the information about the migrations error reported by Laravel 5.4 due to the long special field. We will share the content for your reference. I will not talk much about it below. Let's take a look at the detailed introduction: Laravel 5.4 has changed the default database c

to add data to the table. Add data to the table, INSERT statements like database tablesB = BookInfo() b.btitle = ‘abc b.save() Modify table data, similar to a table update operationB = BookInfo.objects.get(pk=1) pk是主键 primarykehy b.btitle =‘abc‘ b.save() Query tableBookInfo.objects.all() Delete a tableb.delete() BookInfo.objects.all() 查看结果 The test flow is as follows:A virtual environment to create a project test4 and application Book

exists in the database with an enum-type field when the component is integrated, the migration command will be executed with an error.To solve this problem, we need to map the enum to a string type:$connection->getDatabasePlatform()->registerDoctrineTypeMapping(‘enum‘,‘string‘);ConclusionAt this point, we have completed all migration of the migration component and have been able to use it well in the project.The current integration is a version management approach, which is supported by the mig

Recently, the team put forward an egg-ache requirement to turn the 32-bit project into 64-bit, and to produce debug x86, Debug x64, Release x86 release x64 these 4 versions, and do not need anycpuAfter a few days of groping, found that for third-party C + + and other DLLs very good processing, direct replication, covering the past can be, but C # itself we through using the DLL because it will generate information records, so noHowever, the dll,64-bit program for the C#32 bit can actually be cal

But enable-migrations is wrong, ask everyone to answer the next. The error code is as follows: Pm> enable-migrationsGet-package: Could not find parameter matching parameter name "ProjectName".Location E:\TempProject\ADO.NET Entityframework\codefirstnewdatabasesample\packages\entityframework.5.0.0\tools\ entityframework.psm1:611 characters: 40+ $package = Get-package-projectname + categoryinfo:invalidargumen

I. Migration creating data tables and populating data with Seeder databases Database Migrations are like 版本控制 databases that make it easy for your team to modify and share the database structure of your application 1.1 Creating a migration PHP artisan make:migration create_users_table--create=usersphp artisan make:migration add_votes_to_users_table-- Table=users//Add Field The new migration file will be placed in the database/

Because the new project is being re-planned, the database table structure is not the same as it used to be, but I want to save a lot of previous user certifications.So I looked at the Django Import and Export feature.~~~~~~~~~~~~~~~~~~~Data import:Auth.jsonTo export user data:Python manage.py dumpdata auth > Auth.jsonIf the following error occurs, you need to change all the errors in the JSON file ("Content_Type": 18), because the data tables are different, so some errors are understandable.You

The error is as follows:Online said the way to try, and then I uninstalled all NuGet package from the beginning, finally found the problem, in the "add-migration" This step, do not worry about the implementation of instructions, first reboot VS, and then execute the instructions can be restarted before restarting the project can be rebuilt.This means restarting vs after creating some column steps such as the data Model, config file, and so on.UWP-fix in use entityframeworkcore instruction "Add-m

1. Subject design Dblink to soa-suite the premise is that the Dblink both sides have a separate interface table, the effect of migration is, by a mediator trigger event , after this event triggered by the BPEL part to capture this event, Within this BPEL component, the Dblink functions of logging, data reading, data conversion, and data writing are accomplished through the collaboration of Dbadapter (log parts, read parts, write parts). 2. Component Planning Mediater Trigger event BPEL completes

Admin user non-interactive creation:" From django.contrib.auth.models import User; User.objects.create_superuser (' myadmin ', ' [email protected] ', ' hunter2 ')' | Python manage.py ShellDatabase migrations that rely on Auth.user:Python manage.py migrate Authpython manage.py MigrateResources:Http://stackoverflow.com/questions/1466827/automatically-create-an-admin-user-when-running-djangos-manage-py-syncdbHttp://stackoverflow.com/questions/29689365/au

Because before the music valley gathered to find the nest, the official website is hung, Online said to run, although someone had contacted me before I said there are their companies take over, but when there are problems in contact, but can not find people. So decided to replace the VPS. Simple record of the use of this VPS migration command. The new VPS is used by the CentOS 32.Change Password after landing After connecting SSH, the first thing is to replace the root password, the command us

://s3.51cto.com/wyfs02/M01/7E/92/wKiom1cEn1zh_ Z5maahx9g2kvpu521.jpg "" 1101 "height=" 651 "/> Enter the name of the disk Select the VHD that you just migrated after you click Open at the VHD URL Tick already included operating system Choose your OS Version 650) this.width=650; "title=" clip_image012 "style=" border-top:0px; border-right:0px; Background-image:none; border-bottom:0px; padding-top:0px; padding-left:0px; border-left:0px; margin:0px; padding-right:0px "border=" 0 "alt=" clip_image01