Wednesday, April 25, 2012 8:27 PM
I need to do a couple of things with my method. I have a list of PersonID's and to them i want to add an AddressID. So when I insert the first new person to the database I want to get the AddressID and after that I need to aply this AddressID to all other Persons which I have in a list stored. Any suggestions how to do this within LINQ? Are it all seperated actions or are there advanced techniques to do this?
Wednesday, April 25, 2012 8:38 PMOn 4/25/2012 4:27 PM, SpaceLama wrote:> Hello,>> I need to do a couple of things with my method. I have a list of> PersonID's and to them i want to add an AddressID. So when I insert the> first new person to the database I want to get the AddressID and after> that I need to aply this AddressID to all other Persons which I have in> a list stored. Any suggestions how to do this within LINQ? Are it all> seperated actions or are there advanced techniques to do this?>> Greetings,>> Spacelama>The Person record should be inserted first and all Address recordsshould be linked to the Person by PersonID as the Address record orrecords are inserted.There is no such thing as you have some existing Address records thatyou need to link to a Person record on some kind of retrieval processafter the Person is added.It should all happen at once Person inserted and Address recordsinserted linked to the Person.
Thursday, April 26, 2012 5:02 AM
I needed to read your message twice, but to be more clear:
I need to insert 1 person. Get his AddressID by a new query. Then Aply this AddressID to the other Persons!?
If I add a person to the database I cant say give me the last added personID with LINQ? I Should keep the user data (firstname/lastname and birthday) to do a new query and add an Address?
Since a short time I have made the Person and the Address table connected with a foreignh key. What should I think of when inserting data with this new future?
Thursday, April 26, 2012 5:08 PMOn 4/26/2012 1:02 AM, SpaceLama wrote:> I needed to read your message twice, but to be more clear:>> I need to insert 1 person. Get his AddressID by a new query. Then Aply> this AddressID to the other Persons!?No that's not correct. You add a Person first, get its ID, you apply itto a Address record tying the Address record (the child) to its Parentrecord. You don't care about the AddressID>> If I add a person to the database I cant say give me the last added> personID with LINQ?Yes you can that's if you are using Linq-2-SQL or ADO.NET EntityFramework. You can get the PersonID right after you insert the Personobject, because the object will have the PersonID property of the Personobject populated after the insert. You can address the Person.PersonIDright after insert and get the new ID assigned to the PersonID property.> I Should keep the user data (firstname/lastname and> birthday) to do a new query and add an Address?There should be no Address record. You can't add an Address record untilyou add the Person to get its PersonID to be applied as a foreign-key tothe Address record before it's inserted. You can't insert an Addressrecord (the child) without the Person (the parent) being inserted first.That's if you have the database table foreign-key constraints setupproperly.>> Since a short time I have made the Person and the Address table> connected with a foreignh key. What should I think of when inserting> data with this new future?>What are you using? Are you using Linq-2-SQL, ADO.NET Entity Frameworkor what?
Thursday, April 26, 2012 6:59 PM
Thanks for the reply. Now I need to figure out how to do all that. :p
I am using Ling 2 SQL. I have an mdf file which contains the DB and I have an dbml file that gives me the oppurtunity to use Linq 2 sql.
I have set the person table to child and the address table to parent. The other way I couldnt do, because it said that the parent cant be nullable if the child aint. Or something...
Thursday, April 26, 2012 10:08 PMOn 4/26/2012 2:59 PM, SpaceLama wrote:> Hello,>> Thanks for the reply. Now I need to figure out how to do all that. :p>> I am using Ling 2 SQL. I have an mdf file which contains the DB and I> have an dbml file that gives me the oppurtunity to use Linq 2 sql.>> I have set the person table to child and the address table to parent.> The other way I couldnt do, because it said that the parent cant be> nullable if the child aint. Or something...>See, this where you are stuck and you don't know what to do.AddressBook object -- ParentPerson object -- a child object to an AddressBook object but a parentto Address object -- multiple Person objects linked to an AddressBook objectAddress object -- a child to a Person object there can multiple Addressobjects linked to a Person objectSo here is the object you have to address in the add and it must allhappen at onetimeAddressBook.Persons.Addresses -- this is the object you are dealing with.var ab = new AddressBook();ab.AddressbookName = "Help me";// setting all the properties the Addressbook objectvar person = new Person();person.FirstName = "Help Me1";// play close attention hereab.Person.Add(person);The Person object within the AddressBook is a collection of Personobjects within the AddressBook object.-----------------------------------------------------So lets do this.var person = new Person();Your person object has been populated already.person.FirstName = "Help Me1";//play close attention here.var address ad = new Address();address.Address1 = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";person.Address.Add(address);The Address object within the Person object is a collection of Addressobjects within the Person object.-----------------------------------------------------So it's this to keep it simple.var addressbook = new AddressBook();populate addressbook properties but do nothing with the Person<collection> property.var person = new Person()populate person properties but do nothing with Address <collection>property.var address = new Address();populate the address propertiesperson.Address.Add(address)var address1 = new Address();populate the address1 propertiesperson.Address.Add(address1);addressbook.Person.Add(person);SaveChanges();---------------------------------------------------------Linq-2-SQL is going to saveAddressBook.Persons.Addresses1) AddressBook object with 1 Person object with Person object havingmultiple Address objects.Linq-2-SQL ties it all together for you and populate foreign-keys byitself.That's what Linq-2-SQL does.What you need is a good book on Linq-2-SQL that's what you need thatwill show you what you need to know about Linq and Linq-2-SQL.
Friday, April 27, 2012 6:35 AM
Thanks for the big explanation. I haven't tried to code it yet, because I dont have time now, but I would like to react on some text that you wrote at this moment.
You said:Address object -- a child to a Person object there can multiple Address
objects linked to a Person object
My tables looks like this:
Persons -> PersonID, FirstName, LastName, etc., AddressID
Address -> AddressID, Street, HouseNumber, etc.
You say that one person can have multiple addressess, but my table is more designed to assign an address to multiple persons. It is just for personal usage. So if i have a family and select all persons and then I want to add that singe AddressID to all persons. So... am I designen my tables wrong? Or am I not understanding it....
Eventually I wanna make another table: Profiles.
Profiles -> e-mail, mobile number, linkedin, facebook, etc.
I cant have multiple profiles on 1 person. So this means that I should implement the PersonID to the Profiles table as a property identifier?
- Edited by SpaceLama Friday, April 27, 2012 6:38 AM
Friday, April 27, 2012 6:41 AM
Linq itself is an expression language to query collections.
However, it is often also named as Linq to SQL and Linq to Ententities, for which a wizard is created which create a bunch of designer generated code to handle the database with many methods which are not even Linq
One of the Microsoft forums for that is
I (and probably more who know where they talk about) have no idea what you are using. It can even be datasets which you handle with Linq or a mapped solution for which you do the same.
- Marked As Answer by Lie YouModerator Wednesday, May 09, 2012 2:55 AM
Friday, April 27, 2012 12:42 PM
Oke, then I am gladly to tell u how I have made my DB. And if it aint clear after my post. Please let me know how to find out what kind of DB I have.
At the moment I am using a .mdf file. So this means it is a SQL database ? Or is it an mapped database that is similar to the SQL Server Databases?
Second I created an dbml file. I dragged both tables onto it. Then I selected the Person table and added a foreign key relationship. I also tried to apply this within the mdf file to select a table and add this relationshop, but when I dragged my tables into the dbml file i didnt saw a relationship. So I have a foreign key relationship made in the dbml and actually it is called an association, but it looks the same.
When I hoover over the association i see the following:
Address.Person -> Person
Address <- Person.Address
So this means the parent class is Address and child class is Peson and both have the properties of AddressID.
I even got a other association, but I actually dont know how it got there. Maybe it was generated when I made the table... the association looks like this:
Address.Address -> Address
Address <- Address.Address1
That's that about the table generation and relationship part. After that I created two stored procedures:
InsertPerson - parameters: firstname, lastname, addressID
InsertAddress - parameters: street, housenumber, etc
Is it now more clear what kind of database I have?