What do i need to do in order to be able to query across multiple databases which are in the same db engine?
I have added the .edmx file of 1 database, but i only need 1 view from another db.
Thanks in advance!
Here are a couple of options:
Depending on your database platform, make the view from your second database available in your first database. If you're using SQL Server, you can use a linked server. If you're using Oracle, you can use a DB Link. Simply create a view in your main database where the view's select statement utilizes the linked server or db link to reference the view from your second db.
Create a second .edmx file for your second database. This is the route I chose recently. However I was dealing with one SQL Server DB and one was Oracle DB. There were also multiple tables and functions from both being used. I determined that it was cleaner in my case to create two separate data access projects, one for each DB, each with it's own .edmx.
Hope this helps.
Related
We are doing some CRUD operation in DEV environment and data is saved in database. For other environments(like Staging/Prod) we want to copy those records from DEV database and paste to Staging/Prod when required using asp.net MVC. Is it possible? Could you please suggest some pathway in order to accomplish this?
You can accomplish this using a linked server:
https://learn.microsoft.com/en-us/sql/relational-databases/linked-servers/create-linked-servers-sql-server-database-engine?view=sql-server-ver15
This involves creating a link between one database server and another (they must be able to see each other on the network). You can then reference the linked server like this:
INSERT INTO [LinkedServerName].[Database].[dbo].[Table] (......
Alternatively you could use a paid for tool like SSMS tools which can generate insert statements on a per table basis: https://www.ssmstoolspack.com/
My ASP.NET project is using SQL Server as the database. I am wondering if it is possible to store a temporary instance of my database so that I would only need to query once to work with the data that I need. For example, I will query the 2 tables, Person and Students with a common id. I want to be able to join the tables and use the information.
I think there are some solutions:
Store the tables in the front end and use ajax javascript to manipulate the tables information.
Store in a txt file or similar file on to the project folder as a pseudo database.
Would love to hear any ideas!
You could do worse than consider SQL Server Compact edition:
https://www.microsoft.com/en-za/download/details.aspx?id=17876
Which has a small footprint and supports private deployment of its binaries within the application folder
EDIT:
It seems CE is deprecated since last I used it. and MS now recommend SQL Server Express Local DB
https://learn.microsoft.com/en-gb/sql/database-engine/configure-windows/sql-server-express-localdb?view=sql-server-2017
And there is also SQLLite: https://www.supinfo.com/articles/single/6941-an-aspnet-core-mvc-app-with-sqlite-and-entity-framework
I want to add a module build on Code First to a running website, which already has an database. If I set my module to run on separated database, it works fine.
But my friend want to just "add" tables created by my modules to existing database, without adding a new database.
Is there anyway to archive that?
The solution is simple and very easy:
Run the module to create a new, clean database
Use SQL Server to generate sql scripts that create tables of that database. I personally think the metadata table is not needed
Run those scripts against target database
Modify the connection string to point to target database
Now it runs flawless! I'm so happy
Thank you.
I've got remote databases on hosting. Can Flash Builder generate Spark Form with similar structure from database table?
Your Flex application will call a backend script that will access your table definition. Depending on your database, statements will differ.
Here is an example using MySQL: "SHOW COLUMNS FROM MyTable"
Your application will then iterate on the results and generate fields according to your logic.
Basically yes. 1st of all you need to connect to the service which u are providing from your backend, and then check the follow article :
http://flexedup.wordpress.com/2009/10/12/form-generation-in-flash-builder-4/
I want to add the new tables to dbml file dynamically from another database
Thank you
You won't be able to do this. A DataContext is intended to encapsulate a single database - or part of a single database.
If this is a SQL Server database, and the second database is on the same server, I'd suggest creating a view in the first database that selects data from a table in the second one.
Yes only one database is supported with LINQ to SQL. You can use a separate data context file though for this database. But you can't use both contexts in the same query, so you can't join across both databases. You can, however, use queries in stored procedures and join across both databases there, provided they are on the same server or a link server is setup in SQL Server.
HTH.