I am new in MVC3 i am going to create a MVC3 test project where i am create model class name WhiteAccount with ID,Name,Email,Password property. and successfully create a DB but when i add another new property in that WhiteAccount model class and in my DB table too but it give me some error. Some people say just delete the EDMmetadata table from your DB, But Here is the problem i have no EDMmetadata table in my DB ! I create my DB by EntityFramework v4.3.1 system automatically (CodeFirst). What should i do now ?
Check for the __MigrationHistory table.
Open the nuget package manager console and run
update-database -script
It will likely give you a message about having to enable it first, follow those directions
Run: Enable-Migrations
some more info on migrations
http://blogs.msdn.com/b/adonet/archive/2012/02/09/ef-4-3-code-based-migrations-walkthrough.aspx
Im gathering this table is there in your db (under system tables) and it contains your model information. Since your project changed you need to tell the migrations about the new field or delete the table (__MigrationsHistory)
Related
I'm using Sequel::Model. My model has a set_schema block and a create_table call, so the database is completely managed by the model. The database is sqlite.
I'm trying to add columns to the database and I can't find a way to. Adding fields to the schema has no effect. Adding a migration or an alter_table call doesn't do anything. I've asked on IRC and read the docs. I can't find an example of anyone doing this, but it seems simple.
How do I add a column/field to a Sequel Model?
I did a bunch of research and talked to Jeremy Evans. I was going about this wrong. The right way to do this was to remove my schema plugin code and create_table block and move to using migrations. The steps I went through were:
Remove the schema code (create_table, set_schema) from my modesl
Dump the schema from my current sqlite data files into initial migrations into migration files via the sequel -d command
Create a new migration that adds the columns I need via add_column calls in an alter_table block in a change block
Apply the migrations via the sequel -m command
Create rake tasks to run the migrations and hook those tasks into my deploy tasks
I attached an .mdf file in SQL Server 2008 and used that database for my entity framework database first project. Below is the error I got
Exception Details: System.Data.MappingException: Schema specified is not valid.
Error 2062: No mapping specified for instances of the EntitySet and AssociationSet in the EntityContainer"
I tried this link: How do I correctly set an association between two objects in the Entity Framework 4 Entitydesigner?
but it did not work for me. can anyone help me what can be the problem.
thanks,
michaeld
This exception usually occures if you have an entity in your model which doesn't mapped to a table (or an object) into the Database.
If you want that your project just starts debugging, Remove all entities from your model, Right-click in model designer and choose Update model from database
If you have an entity which it supposed to be mapped to a table into database, you should create a relative table in database, and map your entity to that table. You also can ghange your approach from db-first to code-first and enable migrations so that EF updates your db according to your model.
If you have an entity and you want to map it to a stored procedure in your db, see here
I have created a datatbase "testschema" and schema called "MySchema". I have
created a table "MySchema.table1" in the database. I am trying to create sql
cache dependancy on table using aspnet_regsql utitlity.
MySchema.Table1
But it throw an error.
Enabling the table for SQL cache dependency.
An error has happened. Details of the exception:
Cannot create trigger
'dbo.MySchema.Table1_AspNet_SqlCacheNotification_Trigger'
as its schema is different from the schema of the target table or view.
Failed during cache dependency registration.
Please make sure the database name and the table name are valid. Table names
mus
t conform to the format of regular identifiers in SQL.
The failing SQL command is:
dbo.AspNet_SqlCacheRegisterTableStoredProcedure
I have tried with out schema name and again it is failed. Pl. let me know
what's wrong creating dependancy on table?
Found it !
http://forums.asp.net/t/1249281.aspx/1
The problem occured if you have more other schema on your db (other than [dbo])
after the change made to the sp AspNet_SqlCacheRegisterTableStoredProcedure
to select the schema dynamically it worked!
Thank you Vivek
I am currently trying to setup an ASP.Net MVC 3 Application for the first time. I know what I am doing with Ruby on Rails but completely lost with ASP.Net. I would like the app to create the database but not sure what I am doing wrong. I have an empty Database build called ssDB. I have setup the connectionStrings and built out the Model classes. According to everything I have read thus for, when I go to the run the App it should create the database but it doesn't look that way.
The Abbreviated Error I get is:
InnerException: System.Data.SqlClient.SqlException
Message=Invalid object name 'dbo.Users'.
Source=.Net SqlClient Data Provider
ErrorCode=-2146232060
Class=16
LineNumber=1
Number=208
Procedure=""
Server=TESTSVR01
State=1
I have an empty Database build called ssDB
You have created an empty database with no tables. Since there is a database EF assumes tables are also created. Hence it will not proceed to create the tables.
You can drop the database and allow EF to create the database and the tables.
I also experienced the same issue while using Database first approach. Connection string in my service's/service's host web.config was incorrect. I corrected the connection string and it worked.
Suppose I have a database containing 3 tables in a grails application:
User
Activity
Friend
User table table has one to many relation to Activity and Friend tables so in User table I have:
static hasMany = [activies: Activity, friends: Friend]
and in Friend and Activity I have:
static belongsTo User.
Application is deployed and lets says thousands of customers have registered. Now changes are made in the database: Table Activity is dropped. A table Journal is created which is on the many sides of the User table. The User table has a new column added and this column cannot be null. An old column in Friend table is deleted that was also defined as not null.
So given above scenario and assume using MySQL what needs to be done to make above changes without deleting existing customers data and safely add the new table to existing customers?
Ruby on Rails comes with ActiveRecord for database migrations. Does Grails comes with something like this out of the box?
Currently in development when I run my grails application after adding a new not null column to a table, I get column cannot be null exception thrown unless I delete that table in the database before running grails application which would recreate the table if not exists. Obviously once the application is deployed I will not have the luxury to delete the table.
Unfortunately, the current version of Grails doesn't come with database migration. However, there is a plugin for Liquibase which makes migrations possible.
The next version of Grails (1.4, planned for Q1 2011) will supposedly contain a built-in migration tool, which I am very much looking forward to.
Note: I haven't used the Liquibase plugin, so I don't have any firsthand experience with it. I have seen numerous blog posts describing its use, however, and I'm probably going to use it in my next Grails project if 1.4 isn't out by then.