Search Results

Search found 8156 results on 327 pages for 'generic relationship'.

Page 74/327 | < Previous Page | 70 71 72 73 74 75 76 77 78 79 80 81  | Next Page >

  • Unique Keys not recognized by Entity Framework

    - by David Pfeffer
    I have two tables, Reports and Visualizations. Reports has a field, VisualizationID, which points to Visualization's field of the same name via a foreign key. It also has a unique key declared on the field. VisualizationID is not nullable. This means the relationship has to be 0..1 to 1, because every Reports record must have a unique, not null Visualizations record associated with it. The Entity Framework doesn't see it this way. I'm getting the following error: Error 113: Multiplicity is not valid in Role 'Report' in relationship 'FK_Reports_Visualizations'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be *. What's the problem here? How can I make the EF recognize the proper relationship multiplicity?

    Read the article

  • Databind gridview with LINQ

    - by Anders Svensson
    I have two database tables, one for Users of a web site, containing the fields "UserID", "Name" and the foreign key "PageID". And the other with the fields "PageID" (here the primary key), and "Url". I want to be able to show the data in a gridview with data from both tables, and I'd like to do it with databinding in the aspx page. I'm not sure how to do this, though, and I can't find any good examples of this particular situation. Here's what I have so far: <%@ Page Title="Home Page" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="LinqBinding._Default" %> <asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent"> </asp:Content> <asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent"> <h2> Testing LINQ </h2> <asp:GridView ID="GridView1" runat="server" DataSourceID="LinqDataSourceUsers" AutoGenerateColumns="false"> <Columns> <asp:CommandField ShowSelectButton="True" /> <asp:BoundField DataField="UserID" HeaderText="UserID" /> <asp:BoundField DataField="Name" HeaderText="Name" /> <asp:BoundField DataField="PageID" HeaderText="PageID" /> <asp:TemplateField HeaderText="Pages"> <ItemTemplate <asp:DropDownList ID="DropDownList1" DataSourceID="LinqDataSourcePages" SelectedValue='<%#Bind("PageID") %>' DataTextField="Url" DataValueField="PageID" runat="server"> </asp:DropDownList> </ItemTemplate> </asp:TemplateField> </Columns> </asp:GridView> <asp:LinqDataSource ID="LinqDataSourcePages" runat="server" ContextTypeName="LinqBinding.UserDataContext" EntityTypeName="" TableName="Pages"> </asp:LinqDataSource> <asp:LinqDataSource ID="LinqDataSourceUsers" runat="server" ContextTypeName="LinqBinding.UserDataContext" EntityTypeName="" TableName="Users"> </asp:LinqDataSource> </asp:Content> But this only works in so far as it gets the user table into the gridview (that's not a problem), and I get the page data into the dropdown, but here's the problem: I of course get ALL the page data in there, not just the pages for each user on each row. So how do I put some sort of "where" constraint on dropdown for each row to only show the pages for the user in that row? (Also, to be honest I'm not sure I'm getting the foreign key relationship right, because I'm not too used to working with relationships). EDIT: I think I have set up the relationship incorrectly. I keep getting the message that "Pages" doesn't exist as a property on the User object. And I guess it can't since the relationship right now is one way. So I tried to create a many-to-many relationship. Again, my database knowledge is a bit limited, but I added a so called "junction table" with the fields UserID and PageID, same as the other tables' primary keys. I wasn't able to make both of these primary keys in the junction table though (which it looked like some people had in examples I've seen...but since it wasn't possible I guessed they shouldn't be). Anyway, I created a relationship from each table and created new LINQ classes from that. But then what do I do? I set the junction table as the Linq data source, since I guessed I had to do this to access both tables, but that doesn't work. Then it complains there is no Name property on that object. So how do I access the related tables? Here's what I have now with the many-to-many relationship: <%@ Page Title="Home Page" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="ManyToMany._Default" %> <asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent"> </asp:Content> <asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent"> <h2> Many to many LINQ </h2> <asp:GridView ID="GridView1" runat="server" DataSourceID="LinqDataSource1" AutoGenerateColumns="false"> <Columns> <asp:CommandField ShowSelectButton="True" /> <asp:BoundField DataField="UserID" HeaderText="UserID" /> <asp:BoundField DataField="Name" HeaderText="Name" /> <asp:BoundField DataField="PageID" HeaderText="PageID" /> <asp:TemplateField HeaderText="Pages"> <ItemTemplate> <asp:DropDownList ID="DropDownList1" DataSource='<%#Eval("Pages") %>' SelectedValue='<%#Bind("PageID") %>' DataTextField="Url" DataValueField="PageID" runat="server"> </asp:DropDownList> </ItemTemplate> </asp:TemplateField> </Columns> </asp:GridView> <asp:LinqDataSource ID="LinqDataSource1" runat="server" ContextTypeName="ManyToMany.UserPageDataContext" EntityTypeName="" TableName="UserPages"> </asp:LinqDataSource> </asp:Content>

    Read the article

  • django-admin: creating,saving and relating a m2m model

    - by pastylegs
    I have two models: class Production(models.Model): gallery = models.ManyToManyField(Gallery) class Gallery(models.Model): name = models.CharField() I have the m2m relationship in my productions admin, but I want that functionality that when I create a new Production, a default gallery is created and the relationship is registered between the two. So far I can create the default gallery by overwriting the productions save: def save(self, force_insert=False, force_update=False): if not ( Gallery.objects.filter(name__exact="foo").exists() ): g = Gallery(name="foo") g.save() self.gallery.add(g) This creates and saves the model instance (if it doesn't already exist), but I don't know how to register the relationship between the two?

    Read the article

  • ERD Design help meeded

    - by Mobi
    Hello guyz, I am new to ERD and stuff.Earlier i was drawing an erd that issued me some problems. the name of two entities in focus is "Bus" and "Passenger".What shall be the relationship between them. I think it should be many to many since one passenger can travel in many buses and a bus can give ride to many passengers.But one of my friend insisted that its a one-to-many relationship(A bus can have many passengers but a passenger can travel in only one bus).Plz let me know what's right. Also , whats the relationship between a class,students. Any help is appreciated.

    Read the article

  • Questions about "interrupt"

    - by smwikipedia
    Could someone help me clarify the following conecpts, and the relationship among them? Maskable interrupt Unmaskable interrupt Hardware interrupt Software interrupt CPU INTR pin the IF bit of EFlags register Some specific questions: What's the relationship between Maskable/Unmaskable interrupt and Hardware/Software interrupt? What's the relationship between maskability and being software/hardware? Is there any unmaskable/software interrupt and maskable/hardware interrupt? What kind of interrupts does INTR pin detect? What kind of interrupts are enabled/disabled by IF bit of EFlags register? What kind of interrupts need the presence of an interrupt controller? Many thanks.

    Read the article

  • iPhone Development - Query related records using CoreData

    - by Mustafa
    I have a case where i have three entities with one-to-many and one-to-many relationships: Entity A (Entity B relationhip), Entity B (Entity A relationship, Entity C relationship), Entity C (Entity B relationhip) I have the reference of Entity A, and now i want to fetch all the related Entity C records. How can i do that? (with least amount of code) Edit: Here's another way to put it. Can we perform joins with CoreData. For example, (and this is a very crude example), We have a following entity-relationship: Grand Parent (1)---(m) Parent Parent (1)---(m) Child So, now if i have "Albert" the Grand Parent, and i want to get all his grand children, how can i do that?

    Read the article

  • Writing annotataion schemas for Callisto

    - by Ken Bloom
    Does anybody know where I can find documentation on how to write annotation schemas for Callisto? I'm looking to write something a little more complicated than I can generate from a DTD -- that only gives me the ability to tag different kinds of text mentions. I'm looking to create a schema that represents a single type of relationship between five or six different kinds of textual mentions (and some of these types of mentions have attributes that I need to assign values to), and possibly having a second type of relationship between the first two instances of the first type of relationship. (Alternatively, does anybody know of any software that would be better for this kind of schema? I've been looking at WordFreak, but it's a little clumsy, and it doesn't support attributes on its textual mentions.)

    Read the article

  • What are the "Navigation Properties" in this data model for?

    - by d03boy
    I've been wondering how to properly set up many-to-many relationships in ASP.NET MVC 2 using Linq2Sql for quite some time now. I found this blog post that seems to have a similar model layout as mine. If you take a look at the first screenshot showing the data model you can see that each model has "Navigation Properties" at the bottom of it. What exactly is this and why don't my models have them? I have the proper foreign keys put in to place. Most specifically, I am looking at the relationship between the Article and Category models since that is the only many-to-many relationship that I see and that's what I'm trying to model. Obviously I use an intermediary joining table between these two tables but I am having trouble understanding the proper methodology for modeling that relationship and I'm not finding this information anywhere on The Google.

    Read the article

  • What are appropriate ways to represent relationships between people in a database table?

    - by Emilio
    I've got a table of people - an ID primary key and a name. In my application, people can have 0 or more real-world relationships with other people, so Jack might "work for" Jane and Tom might "replace" Tony and Bob might "be an employee of" Rob and Bob might also "be married to" Mary. What's the best way to represent this in the database? A many to many intersect table? A series of self joins? A relationship table with one row per relationship pair and type, where I insert records for the relationship in both directions?

    Read the article

  • Converting legacy GRUB menu entries to GRUB 2

    - by WindowsEscapist
    I would like to change an entry for a solution to boot from CD from legacy grub (looks like title bla bla bla) to an entry to a format compatible to grub 2 (the one that looks like menuentry "bla bla bla" {. The original legacy GRUB entry is as follows: title Boot From CD/DVD Drive kernel /boot/grub/memdisk.din initrd /boot/grub/sbootmgr.dsk Is there any sort of conversion rule to change this to something like the example I've put here on the next line? (This is from my precise's grub.cfg.) menuentry 'Ubuntu, with Linux 3.2.0-25-generic' --class ubuntu --class gnu-linux --class gnu --class os { recordfail gfxmode $linux_gfx_mode insmod gzio insmod part_msdos insmod ext2 set root='(hd0,msdos8)' search --no-floppy --fs-uuid --set=root efc87ac0-daac-4a32-9a85-ea57beff0e28 linux /boot/vmlinuz-3.2.0-25-generic root=UUID=efc87ac0-daac-4a32-9a85-ea57beff0e28 ro quiet splash acpi_osi= $vt_handoff initrd /boot/initrd.img-3.2.0-25-generic }

    Read the article

  • VMWare tools on Ubuntu Server 10.10 kernel source problem

    - by Hamid Elaosta
    After install and running the vm-ware config, the config needs my kernel headers to compile some modules, ok, so I'll give it them, but it just won't work. It asks for the path of the directory of C header files that match my running kernel. If I uname -r I get 2.6.35-22-generic-pae So I tell it the source path is /lib/modules/2.6.25-22-generic-pae/build/include and it returns "The directory of kernel headers (version @@VMWARE@@ UTS_RELEASE) does not match your running kernel (version 2.6.35-22-generic-pae). ..I'm confused? can anyone offer suggestions please? I installed hte kernel source andh eaders myself using sudo apt-get install linux-headers-$(uname -r)

    Read the article

  • Bluetooth radio device is not available

    - by Mike
    I reinstalled my Windows 7 operating system, and have since been unable to detect my Logitech m555b bluetooth mouse. Here is some info about my system: I have have a working connection with a bluetooth printer. I have a message in the "My Bluetooth" section of explorer stating "Bluetooth radio device is not available". The Device Manager indicates that the Generic Bluetooth radio is working correctly. The bluetooth "F12" switch is on. Mouse batteries are new and the right way around. I'm presuming that I need a bluetooth driver which is non generic. The computer is a Clevo P150HMx (the version with the GTX485 GPU) with the default WLAN / bluetooth combo card manufactured by Realtek (I think it's a Realtek RTL8188CE card). I think I have the drivers installed, but I still get the generic driver in the Device Manager. I'm confused. Please help, I'm going mad on the touchpad. (Thanks for the touchup wizlog)

    Read the article

  • How do I get a right outer join in L2E?

    - by Dan
    I have two tables that I set up through the VS Entity Data Model Diagram tool. I'm trying to do a right outer join and it doesn't return results from the 2nd table. I have set up a 0..1 to MANY relationship from the diagram tool. When I run a Linq-To-Entities query, it still defaults to an INNER JOIN. From my understanding of entities, if I set up the relationship using VS, when I join the tables, it should automagically figure out the join syntax based on the relationship I supply. It doesn't seem to be doing that. I am using EF v1 (not Linq-to-Sql). Query I'm running: from s in SomeTable join t in SomeOtherTable on s.ID equals t.ID select new { s.MyFieldName, t.MyOtherFieldName }

    Read the article

  • How to manually manage Core Data relationships when deleting

    - by Simon
    I have a Core Data entity, which contains a relationship to another entity. Under certain circumstances, I need to delete the managed objects in the relationship, and at other times no action needs to be taken. I have the Delete Rule on the entity is No Action because of this manual management. The problem I have is, where is the best place to enforce these rules? I cannot see any suitable messages to override on NSManagedObject (something that might notify the object it has been deleted and should clear up its relationships). I would rather not do it higher up in the application logic, because the entity objects can get deleted from array controllers and at different points in the applications, making it necessary to stuff relationship update code at all those levels.

    Read the article

  • Address rewriting postfix

    - by ACHAL
    I am using CentOs5 and postfix as an MTA for my server. My situation is as follows:- I have a mail server through which Php applications connect and send mails to the destination addresses. The problem is that the the application servers do not have spf/dkim record set up and my server which actually relays the mails to the network has spf/dkim records. So i want the mail sent by an application having a return address:[email protected] to change to [email protected]. r09.4reseller.org is hostname of my mail server. This i have done by generic mapping in postfix: smtp_generic_maps = hash:/etc/postfix/generic In /etc/postfix/generic: [email protected] [email protected] This is working as return address is changed to [email protected] when mail is sent. But when i try to sent mail on [email protected] I don't get mail on [email protected]. I have tried virtual mapping in postfix i.e by the file /etc/postfix/virtual but its not helping.

    Read the article

  • VMWare tools on Ubuntu Server 10.10 kernel source problem

    - by Hamid Elaosta
    After install and running the vm-ware config, the config needs my kernel headers to compile some modules, ok, so I'll give it them, but it just won't work. It asks for the path of the directory of C header files that match my running kernel. If I uname -r I get 2.6.35-22-generic-pae So I tell it the source path is /lib/modules/2.6.25-22-generic-pae/build/include and it returns "The directory of kernel headers (version @@VMWARE@@ UTS_RELEASE) does not match your running kernel (version 2.6.35-22-generic-pae). ..I'm confused? can anyone offer suggestions please? I installed hte kernel source andh eaders myself using sudo apt-get install linux-headers-$(uname -r)

    Read the article

  • Possible to get PrimayKey IDs back after a SQL BulkCopy?

    - by chobo2
    Hi I am using C# and using SqlBulkCopy. I have a problem though. I need to do a mass insert into one table then another mass insert into another table. These 2 have a PK/FK relationship. Table A Field1 -PK auto incrementing (easy to do SqlBulkCopy as straight forward) Table B Field1 -PK/FK - This field makes the relationship and is also the PK of this table. It is not auto incrementing and needs to have the same id as to the row in Table A. So these tables have a one to one relationship but I am unsure how to get back all those PK Id that the mass insert made since I need them for Table B.

    Read the article

  • Monitor resolution messed up somehow

    - by Kelp
    I purchased the Westinghouse 22" LCD LCM-22w3 a few years ago, and now it's been acting up on me. I just booted into Windows 7(without changing any settings), and the default resolution is 1600x1024, and it allows me to select a refresh rate of up to 85 Hz(it didn't let me do that). I usually have my resolution set to 1680x1050 with a refresh rate of 60 Hz. Now, that resolution does not even appear in the list. Does anyone have any idea of what could be the problem and how to fix it? Edit: I am not sure if this will help, but when I go to change the screen resolution, the monitor is known as "Generic Non-PnP Monitor". It used to be referred to as "Generic PnP Monitor). I tried to disable Generic Non-PnP Monitor, but when I restart, it uses that monitor again. Edit 2: I created a custom .inf file using Powerstrip, but that does not work either. The monitor settings are being stubborn.

    Read the article

  • CoreData: Sort and Section on Relationships

    - by David.Chu.ca
    I have two questions about using Core Data. Taking the typical case of Employee and Department as an example. The Employee entity has a relationship field "deparment" as to-one to Department, and the Department entity has a relationship "employee" as to-many to Employee entity. I would like to display all the employees in a TableView in sections of department's names. I think that the NSFetchedResultsController should use Employee as entity. I am not sure how to use Department's name as a sort criteria, since it is in an employee's relationship field department's name. Can you use "DepartmentName" as a sort and add this to Employee entity class as a method which will return department's name for a given employee? The second question is the section name. I would like to use department names as sections. Can I use the above method as sectionKeyPath's value for the NSFethedResultsController? Not sure if I am on the right track.

    Read the article

  • Injecting relationships in DBIx::Class

    - by Carl
    I have a handful of DBIx::Class::Core objects that model various database tables. For some of those models (those that have a 'queue' column), I have another class inject subs (basically, to 'move' the model object along it's queue states). I'd like to also have that class inject has_many relationships ala class($name)->has_many('queue_history','MySchema::Result::QueueHistory', { 'foreign.record_id'=>'self.id' }, { where => { type => $name }} ); but I can't seem to get the relationships to register properly (keep getting "No Such Relationship" errors - however, when calling the relationship method on the sources provides back the relationship). Any clues as to what's wrong?

    Read the article

  • Using NSPredicate to filter on both Core attribute and entity

    - by Ben Thompson
    I have two entities in core data (call them entityOne and entityTwo). I have a entityOne<---entityTwo relationship between them. I am now trying to code an NSPredicate to fetch entityTwo objects on the following basis: Fetch entityTwo objects that have a relationship with a specified entityOne object. Filter out those entityTwo objects which have no value for one of their attributes. I am best doing both of these in an NSPredicate or is there a better way? I am trying the following: NSPredicate *predicate = [NSPredicate predicateWithFormat:@"(attribute <> "") AND (relationship == entityOne"]; [request setPredicate:predicate]; Any pointers on coding great fully received.

    Read the article

  • Database design efficiency with 1 to many relationships limited 1 to 3

    - by Joe
    This is in mysql, but its a database design issue. If you have a one to many relationship, like a bank customer to bank-accounts, typically you would have the table that records the bank-account information have a foreign key that keeps track of the relationship between account and customer. Now this follows the 3rd normal form thing and is a widely accepted way of doing it. Now lets say that you are going to limit a user to only having 3 accounts. The current database implementation will support this and nothing would need to change. But another way to do this would have 3 coloms in the account table that have the id of the 3 respective accounts in them. By the way this violates 1st normal form of db design. The question is what would be the advantage and disadvantages of having the user account relationship recored in this way over the traditional?

    Read the article

  • How to represent a 3-way relation with JPA?

    - by simpatico
    A user may have several labels, and links. Then, a user associates a label (or more) to a link. How does one represent the later relationship? A solution could be a many-to-many relationship btw user and link with the optional attribute label. http://en.wikibooks.org/wiki/Java_Persistence/ManyToMany#Mapping_a_Join_Table_with_Additional_Columns In this case the relationship btw user and label may better be 'virtual'. Any alternative I'm not seeing? PS: I've used google bookmarks terminology, as it matches my case quite well.

    Read the article

  • list and explanations of ways to boost this router's signal strength? [closed]

    - by barlop
    Possible Duplicates: Improve Wireless Signal How to get wireless coverage over my whole house? What's the best way to increase the range of my 802.11g router? The back of my house doesn't have WiFi Signal I'm interested in ways that are both specific to certain routers, and generic. When I say generic, I don't necessarily mean a one way that works for many.. but it can also be a generic answer, so mentioning solutions for different situations. So not just the one router I mention. Explanations are important, as well as all the ways. One i'm particularly interested in boosting the strength of is this wireless router/modem Netgear VMDG280 maybe anywhere in a big house with three floors, maybe from the garden.

    Read the article

  • fields_for to stop pluralizing.

    - by Dmitriy Likhten
    I have a fields_for tag, where I specify the prefix (lets say for some good reasons), and this is supposed to represent a one-to-one relationship. I am trying to represent a relationship widget has_many thingamagigs thingamagig has_one whatchamacallit The field_for code is: fields_for "widgt[thingamagigs_attributes][][whatchamacallit_attributes]", thingamagig.whatchamacallit do |x| which generates names (wrongly): widget[thingamagigs_attributes][][whatchamacallit_attributes][][value] The better solution would be t.fields_for :whatchamacallit do |x| where t = fields_for the thingamagig... However if I do that, the following names are generated widgt[thingamagigs_attributes][whatchamacallit_attributes][] which is completely wrong as all other fields for a thingamagig is... widgt[thingamagigs_attributes][][name] So in all cases I am screwed. The original field_for using a string cannot be used with accepts_nested_attributes_for :whatchamacallit since whatchamacallit is a singular relationship and an object is expected not an array. The second fields_for will simply not work because rails cannot parse the params object correctly. Is there a way to tell the first forms_for to not add the [] after [whatchamacallit_attributes] in all field names?

    Read the article

< Previous Page | 70 71 72 73 74 75 76 77 78 79 80 81  | Next Page >