Databases :: Multiple Foreign Keys In One Table Referencing The Same Column?
Feb 26, 2011
I use Mysql database, in this i create two table A, B. table A column x and is FK of second table B's column m,n,o provide does it possible that x referncing to foreign key of table B columns m, n , and o all.
My current project has many peripheral systems and many different environments (testing, integration, development etc). As expected, we're using .config files to dynamically manage everything.
Instead of updating each relavant key when deploying to an environment, I was hoping there was a way to change 1 key only. Such as:
I've done some searching and haven't come up with an elegant solution. I'm aware that .config files can make use of system variables, but this seems like a bit of a high wire act.
I have an MVC3 with EF4 project. I have a screen for order .Order has 2 id's inside it for Billilng and Shipping AddressID .When I go and create a new order these fields render as single textboxes as Ids'Question is how can I render full address textboxes (addressline1,city,state,zip etc) do I have drop in the html markup for them? In that case while capturing the data back I willl have to go with classic way of retrieving name/value pair and then do insert into address bring back that identity and update the order record...?
Create(int customerID,FormCollection fc){}
So the main question is how can I do ModelBinding with foreign keys?
I am using Access 2003 Database and I need to retrieve list of a table's foreign keys and tables they are related to in C#. I used GetSchema() function of OleDbConnection as well as OdbcConnection classes. But It just returns the name of key among few other details.
I am developing asp.net MVC3 application and I have following entity
This entity has composite key (CreditRegistryId and Accoubnt No are primary keys). CreditRegistryId is a foreign key as well. How can I make composite key and foreign key. I am using DbContext API from EF 4.1. I am not using edmx ( ORM designer)
I have an EF model with a table with several foreign keys. These foreign keys are managed by associations. In code, I can get a strongly typed list of objects when I access that property on the object.
When I generate a strongly typed view, all I see are the int fields. Is there a way to get ASP.NET MVC to bind to the objects that are related as well as the main object?
I just came across some code that seems to encrypt database keys prior to sending them to the client (WebBrowser, Silverlight, etc).
To illustrate, suppose you have a list of students to extra-curricular activities, and a relationship defined between them. Every time the data is written out to the ASPX page, the studentID and activityID is encrypted. Every time a write, or modify is made, this value is sent back to the server, decrypted, and saved to the database.
What could be the reasons to expose data this way? Is this a normal practice?
I am having trouble with foreign keys Dynamic Data and entity framework 4.0. It feels like there is a problem with the entity association but I am not sure. I have multiple fields representing the foreign key on the insert page.
When I try and insert data I get an error A dependent property in a ReferentialConstraint is mapped to a store-generated column.
Column: 'CommentId'
My data is a very basic one to many relationship, the foreign key in question is BookId in the Comment Table.
[code]...
When I let the scaffolding do its thing, I get multiple fields representing the foreign key.
how to handle foreign keys with Entity Framework, when editing or adding a new record. For example, I have a person table, which has a timezone_id linking to my timezone table.
But the model seems to not include timezone_id. I see it's a new way of doing things, but ... how do I store my record?
My method:
[code]...
I can't do u.timezone_id = timezoneid;
I only have u.timezone (which seems to be the actual entity), and u.timezoneReference, which I am not sure what to do with.
I have the following tables in my database which are as given under:
[code]...
My requirement is instead of getting the PromotionID values displayed for columns CustomerPromotionDiscountID & EmployeePromotionDiscountID, it should display the respective DiscountAmount. Which is not happenning for some reason.
I somehow found a workaround where if i define the datatype for columns CustomerPromotionDiscountID and EmployeePromotionDiscountID as nchar or nvarchar, it displays the DiscountAmount.
Wanted to know if there is any better way of doing this without changing the datatype for my columns?
Adding data into kartlar table (RehberID,KampanyaID,BrimID) is ok. But which Kart'ID created? I need to learn which Id created after adding data (RehberID,KampanyaID,BrimID) into Kartlar?
[code]...
How can I do that? I want to get data from Kartlar which data I added?
Am trying to get a working enity model with foreign keys working but have run into a problem. I have imported 3 tables with content and some data.Lets call these tables geo_countries, geo_counties, geo_municipalities and the FK are:1. geo_county have a column country_id wich corresponds to country_id in geo_country 2. geo_municipality have a column county_id wich correspond to the county_id in geo_county.The problem i have is when i try to get correspondig child items with the following code i run into trouble:
[Code]....
The problem above is that 'test' generates results but not 'test2', wich never return anything. Am i not supposed to be able to do it like i do in 'test2'? I earlier tried to add a child object by replacing ToList() with Add() and that worked. But i cant seem to get anything out of it.
I am retrieving a column from a table using an SqlDataSource in ASP.NET/C#, which contains multiple 'values' separated by commas. I'd like to be able to separate this values into multiple columns in my GridView, and also allow them to update them. Is this easy to accomplish?
I want to copy data from a table[tblExcel][No.of columns:2] to another table[ev_event] which has 5 columns, 2 columns from the another table, 3 columns from user defined value
I can easily create a search that will allow a user to input a single word (or a portion of a single word) into a text box that will search a database column.
But what I want is for the user to be able to type two or three words into the textbox and produce results where just one of the words have to match the contents of the columns cell.
I don't need to be able to do a multi column or table search, and I'm using C# and MS Access.
I imagine this question would have been asked more than a couple of times - but I can't find a decent answer.
what I wanna achieve is to have a statement that selects distinct uniqueid's from the chapterID field and with every duplicate I would like to have the record with the highest version number
I have a dropdownlistbox which references a specific column for a table in my database. After I select the proper id from the dropdownlistbox, I should press the submit button to see the name of the customer populated in a text field who references the id number for the dropdownlistbox. However, I am having trouble referencing a different column within the table. I can only view the selected value from the dropdownlistbox in the text box.