Search Results

Search found 389 results on 16 pages for 'fk'.

Page 13/16 | < Previous Page | 9 10 11 12 13 14 15 16  | Next Page >

  • Best pattern for storing (product) attributes in SQL Server

    - by EdH
    We are starting a new project where we need to store product and many product attributes in a database. The technology stack is MS SQL 2008 and Entity Framework 4.0 / LINQ for data access. The products (and Products Table) are pretty straightforward (a SKU, manufacturer, price, etc..). However there are also many attributes to store with each product (think industrial widgets). These may range from color to certification(s) to pipe size. Every product may have different attributes, and some may have multiples of the same attribute (Ex: Certifications). The current proposal is that we will basically have a name/value pair table with a FK back to the product ID in each row. An example of the attributes Table may look like this: ProdID AttributeName AttributeValue 123 Color Blue 123 FittingSize 1.25 123 Certification AS1111 123 Certification EE2212 123 Certification FM.3 456 Pipe 11 678 Color Red 999 Certification AE1111 ... Note: Attribute name would likely come from a lookup table or enum. So the main question here is: Is this the best pattern for doing something like this? How will the performance be? Queries will be based on a JOIN of the product and attributes table, and generally need many WHEREs to filter on specific attributes - the most common search will be to find a product based on a set of known/desired attributes. If anyone has any suggestions or a better pattern for this type of data, please let me know. Thanks! -Ed

    Read the article

  • Fluent NHibernate - Cascade delete a child object when no explicit parent->child relationship exists

    - by John Price
    I've got an application that keeps track of (for the sake of an example) what drinks are available at a given restaurant. My domain model looks like: class Restaurant { public IEnumerable<RestaurantDrink> GetRestaurantDrinks() { ... } //other various properties } class RestaurantDrink { public Restaurant Restaurant { get; set; } public Drink { get; set; } public string DrinkVariety { get; set; } //"fountain drink", "bottled", etc. //other various properties } class Drink { public string Name { get; set; } public string Manufacturer { get; set; } //other various properties } My db schema is (I hope) about what you'd expect; "RestaurantDrinks" is essentially a mapping table between Restaurants and Drinks with some extra properties (like "DrinkVariety" tacked on). Using Fluent NHibernate to set up mappings, I've set up a "HasMany" relationship from Restaurants to RestaurantDrinks that causes the latter to be deleted when its parent Restaurant is deleted. My question is, given that "Drink" does not have any property on it that explicitly references RestaurantDrinks (the relationship only exists in the underlying database), can I set up a mapping that will cause RestaurantDrinks to be deleted if their associated Drink is deleted? Update: I've been trying to set up the mapping from the "RestaurantDrink" end of things using References(x => x.Drink) .Column("DrinkId") .Cascade.All(); But this doesn't seem to work (I still get an FK violation when deleting a Drink).

    Read the article

  • doublechecking: no db-wide 'unicode switch' for sql server in the foreseeable future, i.e. like Orac

    - by user72150
    Hi all, I believe I know the answer to this question, but wanted to confirm: Question Does Sql server (or will it in the foreseeable future), offer a database-wide "unicode switch" which says "store all characters in unicode (UTF-16, UCS-2, etc)", i.e. like Oracle. The Context Our application has provided "CJK" (Chinese-Japanese-Korean) support for years--using Oracle as the db store. Recently folks have been asking for the same support in sql server. We store our db schema definition in xml and generate the vendor-specific definitions (oracle, sql server) using vendor-specific xsl. We can make the change easily. The problem is for upgrades. Generated scripts would need to change the column types for 100+ columns from varchar to nvarchar, varchar(max) to nvarchar(max), etc. These changes require dropping and recreating indexes and foreign keys if the any indexes/fk's exist on the column. Non-trivial. Risky. DB-wide character encodings for us would eliminate programming changes. (I.e. we would not to change the column types from varchar to nvarchar; sql server would correctly store unicode data in varchar columns). I had thought that eventually sql server would "see the light" and allow storing unicode in varchar/clob columns. Evidently not yet. Recap So just to triple check: does mssql offer a database-wide switch for character encoding? Will it in SQL2008R3? or 2010? thanks, bill

    Read the article

  • ASP.NET MVC Model Binding into a List

    - by Maxim Z.
    In my ASP.NET MVC site, part of a feature allows the user to enter the hours when a certain venue is open. I've decided to store these hours in a VenueHours table in my database, with a FK-to-PK relationship to a Venues table, as well as DayOfWeek, OpeningTime, and ClosingTime parameters. In my View, I want to allow the user to only input the times they know about; in other words, some days may not be filled in for a Venue. I'm thinking of creating checkboxes that the user can check to enable the OpeningTime and ClosingTime fields for the DayOfWeek that the checkbox belongs to. My question relates to how to pass this information to my HttpPost Controller Action. As I know the maximum amount of Days that can be passed in (7), I could of course just write 7 nullable VenueHour parameters into my Action, but I'm sure there's a better way. Can I somehow bind the View information into a List that is passed to my Action? This will also help me if I run into a scenario where there is no limit to how much information the user can fill in.

    Read the article

  • Data in two databases, eager spool resulting in query

    - by Valkyrie
    I have two databases in SQL2k5: one that holds a large amount of static data (SQL Database 1) (never updated but frequently inserted into) and one that holds relational data (SQL Database 2) related to the static data. They're separated mainly because of corporate guidelines and business requirements: assume for the following problem that combining them is not practical. There are places in SQLDB2 that PKs in SQLDB1 are referenced; triggers control the referential integrity, since cross-database relationships are troublesome in SQL Server. BUT, because of the large amount of data in SQLDB1, I'm getting eager spools on queries that join from the Id in SQLDB2 that references the data in SQLDB1. (With me so far? Maybe an example will help:) SELECT t.Id, t.Name, t2.Company FROM SQLDB1.table t INNER JOIN SQLDB2.table t2 ON t.Id = t2.FKId This query results in a eager spool that's 84% of the load of the query; the table in SQLDB1 has 35M rows, so it's completely choking this query. I can't create a view on the table in SQLDB1 and use that as my FK/index; it doesn't want me to create a constraint based on a view. Anyone have any idea how I can fix this huge bottleneck? (Short of putting the static data in the first db: believe me, I've argued that one until I'm blue in the face to no avail.) Thanks! valkyrie Edit: also can't create an indexed view because you can't put schemabinding on a view that references a table outside the database where the view resides. Dang it.

    Read the article

  • how to write this typical mysql query( ho to use subquery column into main query)

    - by I Like PHP
    I HAVE TWO TABLES shown below table_joining id join_id(PK) transfer_id(FK) unit_id transfer_date joining_date 1 j_1 t_1 u_1 2010-06-05 2010-03-05 2 j_2 t_2 u_3 2010-05-10 2010-03-10 3 j_3 t_3 u_6 2010-04-10 2010-01-01 4 j_5 NULL u_3 NULL 2010-06-05 5 j_6 NULL u_4 NULL 2010-05-05 table_transfer id transfer_id(PK) pastUnitId futureUnitId effective_transfer_date 1 t_1 u_3 u_1 2010-06-05 2 t_2 u_6 u_1 2010-05-10 3 t_3 u_5 u_3 2010-04-10 now i want to know total employee detalis( using join_id) which are currently working on unit u_3 . means i want only join_id j_1 (has transfered but effective_transfer_date is future date, right now in u_3) j_2 ( tansfered and right now in `u_3` bcoz effective_transfer_date has been passed) j_6 ( right now in `u_3` and never transfered) what i need to take care of below steps( as far as i know ) <1> first need to check from table_joining whether transfer_id is NULL or not <2> if transfer_id= is NULL then see unit_id=u_3 where joining_date <=CURDATE() ( means that person already joined u_3) <3> if transfer_id is NOT NULL then go to table_transfer using transfer_id (foreign key reference) <4> now see the effective_transfer_date regrading that transfer_id whether effective_transfer_date<=CURDATE() <5> if transfer date has been passed(means transfer has been done) then return futureUnitID otherwise return pastUnitID i used two separate query but don't know how to join those query?? for step <1 ans <2 SELECT unit_id FROM table_joining WHERE joining_date<=CURDATE() AND transfer_id IS NULL AND unit_id='u_3' for step<5 SELECT IF(effective_transfer_date <= CURDATE(),futureUnitId,pastUnitId) AS currentUnitID FROM table_transfer // here how do we select only those rows which have currentUnitID='u_3' ?? please guide me the process?? i m just confused with JOINS. i think using LEFT JOIN can return the data i need, but i m not getting how to implement ...please help me. Thanks for helping me alwayz

    Read the article

  • Django tests failing on invalid keyword argument

    - by Darwin Tech
    I have a models.py like so: from django.db import models from django.contrib.auth.models import User from datetime import datetime class UserProfile(models.Model): user = models.OneToOneField(User) def __unicode__(self): return self.user.username class Project(models.Model): user = models.ForeignKey(UserProfile) created = models.DateTimeField(auto_now_add=True) updated = models.DateTimeField(auto_now=True) product = models.ForeignKey('tool.product') module = models.ForeignKey('tool.module') model = models.ForeignKey('tool.model') zipcode = models.IntegerField(max_length=5) def __unicode__(self): return unicode(self.id) And my tests.py: from django.test import TestCase, Client # --- import app models from django.contrib.auth.models import User from tool.models import Module, Model, Product from user_profile.models import Project, UserProfile # --- unit tests --- # class UserProjectTests(TestCase): fixtures = ['admin_user.json'] def setUp(self): self.product1 = Product.objects.create( name='bar', ) self.module1 = Module.objects.create( name='foo', enable=True ) self.model1 = Model.objects.create( module=self.module1, name='baz', enable=True ) self.user1 = User.objects.get(pk=1) ... def test_can_create_project(self): self.project1 = Model.objects.create( user=self.user1, product=self.product1, module=self.module1, model=self.model1, zipcode=90210 ) self.assertEquals(self.project1.zipcode, 90210) But I get a TypeError: 'product' is an invalid keyword argument for this function error. I'm not sure what is failing but I'm guessing something to do with the FK relationships... Any help would be much appreciated.

    Read the article

  • Require help in Writing Query

    - by harigm
    The following image have been uploaded to show what I am trying to do and what I wanted out of it Can any one help me write the Query to get the results what I want Please check the following SELECT * FROM KPT WHERE PROPERTY_ID IN (SELECT PROPERTY_ID FROM khata_header WHERE DIV_ID = 3 and RECORD_STATUS = 0) and CHALLAN_NO > 42646 The above is the query I have written and I have got the following result set ID CHALLAN_NO PROPERTY_ID SITE_NO TOTAL_AMOUNT ----- ------------- -------------- ------------------- --------------- 1242 42757 3103010141 296 595 1243 63743 3204190257 483 594 1244 63743 3204190257 483 594 1334 43395 3217010223 1088 576 1421 524210 3320050416 (null) (null) 1422 524210 3320050416 (null) (null) 1560 564355 3320021408 (null) (null) 1870 516292 3320040420 (null) (null) 1940 68357 3217100104 139 1153 1941 68357 3217100104 139 1153 2002 56256 3320100733 511 4430 2003 56256 3320100733 511 4430 2004 66488 3217040869 293 3094 2005 66488 3217040869 293 3094 2016 64571 3217040374 (null) (null) 2036 523122 3320020352 (null) (null) 2039 65682 3217040021 273 919 In my resultset, I am getting the PropertyId repeated, since there are multilple entries, How Can I know How many have been repeated What are those Property Id which have repeated more than 2 times. Little Back ground about the tables are PROPERTY_ID is the FK in the KPT PROPERTY_ID is the PK in KH I am writing a subquery to get the Result, so I am stuck I dont know how to get my results Please help

    Read the article

  • Speed up SQL Server Fulltext Index through Text Duplication of Non-Indexed Columns

    - by Alex
    1) I have the text fields FirstName, LastName, and City. They are fulltext indexed. 2) I also have the FK int fields AuthorId and EditorId, not fulltext indexed. A search on FirstName = 'abc' AND AuthorId = 1 will first search the entire fulltext index for 'abc', and then narrow the resultset for AuthorId = 1. This is bad because it is a huge waste of resources as the fulltext search will be performed on many records that won't be applicable. Unfortunately, to my knowledge, this can't be turned around (narrow by AuthorId first and then fulltext-search the subset that matches) because the FTS process is separate from SQL Server. Now my proposed solution that I seek feedback on: Does it make sense to create another computed column which will be included in the fulltext search which will identify the Author as text (e.g. AUTHORONE). That way I could get rid of the AuthorId restriction, and instead make it part of my fulltext search (a search for 'abc' would be 'abc' and 'AUTHORONE' - all executed as part of the fulltext search). Is this a good idea or not? Why?

    Read the article

  • Importing fixtures with foreign keys and SQLAlchemy?

    - by Chris Reid
    I've been experimenting with using fixture to load test data sets into my Pylons / PostgreSQL app. This works great except that it fails to properly create foreign keys if they reference an auto increment id field. My fixture looks like this: class AuthorsData(DataSet): class frank_herbert: first_name = "Frank" last_name = "Herbert" class BooksData(DataSet): class dune: title = "Dune" author_id = AuthorsData.frank_herbert.ref('id') And the model: t_authors = sa.Table("authors", meta.metadata, sa.Column("id", sa.types.Integer, primary_key=True), sa.Column("first_name", sa.types.String(100)), sa.Column("last_name", sa.types.String(100)), ) t_books = sa.Table("books", meta.metadata, sa.Column("id", sa.types.Integer, primary_key=True), sa.Column("title", sa.types.String(100)), sa.Column("author_id", sa.types.Integer, sa.ForeignKey('authors.id')) ) When running "paster setup-app development.ini", SQLAlchemey reports the FK value as "None" so it's obviously not finding it: 15:59:48,683 INFO [sqlalchemy.engine.base.Engine.0x...9eb0] INSERT INTO books (title, author_id) VALUES (%(title)s, %(author_id)s) RETURNING books.id 15:59:48,683 INFO [sqlalchemy.engine.base.Engine.0x...9eb0] {'author_id': None, 'title': 'Dune'} The fixture docs actually warn that this might be a problem: "However, in some cases you may need to reference an attribute that does not have a value until it is loaded, like a serial ID column. (Note that this is not supported by the SQLAlchemy data layer when using sessions.)" http://farmdev.com/projects/fixture/using-dataset.html#referencing-foreign-dataset-classes Does this mean that this is just not supported with SQLAlchemy? Or is it possible to load the data without using SA "sessions"? How are other people handling this issue?

    Read the article

  • MonoRail ActiveRecord - The UPDATE statement conflicted with the FOREIGN KEY SAME TABLE

    - by Justin
    Hey all, I'm new to MonoRail and ActiveRecord and have inherited an application that I need to modify. I have a Category table (Id, Name) and I'm adding a ParentId FK which references the Id in the same table so that you can have parent/child category relationships. I tried adding this to my Category model class: [Property] public int ParentId { get; set; } I also tried doing it this way: [BelongsTo("ParentId")] public Category Parent { get; set; } When I call a method to get all parent categories (they have a null ParentId), it works fine: public static Category[] GetParentCategories() { var criteria = DetachedCriteria.For<Core.Models.Category>(); return (FindAllByProperty("ParentId", null)); } However, when I call a method to get all child categories within a specific category, it errors out: public static Category[] GetChildCategories(int parentId) { var criteria = DetachedCriteria.For<Core.Models.Category>(); return (FindAllByProperty("ParentId", parentId)); } The error is: "The UPDATE statement conflicted with the FOREIGN KEY SAME TABLE constraint \"FK_Category_ParentId\". The conflict occurred in database \"UCampus\", table \"dbo.Category\", column 'Id'.\r\nThe statement has been terminated." I'm hard-coding in the parentId parameter as 1 and I'm 100% sure it exists as an id in the Category table so I don't know why it'd give this error. Also, I'm doing a select, not an update, so what is going on here?? Thanks for any input on this, Justin

    Read the article

  • [hibernate - jpa] @CollectionOfElements without create the apposite table

    - by blow
    Hi all. I have this: Municipality class @Entity public class Municipality implements Serializable { @Id @GeneratedValue(strategy=GenerationType.IDENTITY) private Long id; private String country; private String province; private String name; @Column(name="cod_catasto") private String codCatastale; private String cap; @CollectionOfElements private List<Address> addressList; public Municipality() { } ... Address class @Embeddable public class Address implements Serializable { @ManyToOne(fetch=FetchType.LAZY) @Cascade(CascadeType.SAVE_UPDATE) private Municipality municipality; @Column(length=45) private String address; public Address() { } ... Address is embedded in another class Person. When i save an instance of Person, hibernate create 3 tables: PERSON, MUNICIPALITY and MUNICIPALITY_ADDRESSLIST. MUNICIPALITY_ADDRESSLIST contains 2 fields: MUNICIPALITY_ID (FK) and STREET. I don't want this table, i only want the ID of table MUNICIPALITY into table PERSON(that embeds Address), what should i do? I tried to add @JoinTable in Municipality entity like this: @CollectionOfElements @JoinTable(name="person") private List<Address> addressList; It partially worked, but i cant choose the column name of table PERSON that contains ID of the table MUNICIPALITY, it is, by hibernate choose, simply "MUNICIPALITY_ID"... Thbaks.

    Read the article

  • How to record different authentication types (username / password vs token based) in audit log

    - by RM
    I have two types of users for my system, normal human users with a username / password, and delegation authorized accounts through OAuth (i.e. using a token identifier). The information that is stored for each is quite different, and are managed by different subsytems. They do however interact with the same tables / data within the system, so I need to maintain the audit trail regardless of whether human user, or token-based user modified the data. My solution at the moment is to have a table called something like AuditableIdentity, and then have the two types inheriting off that table (either in the single table, or as two seperate tables with 1 to 1 PK with AuditableIdentity. All operations would use the common AuditableIdentity PK for CreatedBy, ModifiedBy etc columns. There isn't any FK constraint on the audit columns, so any text can go in there, but I want an easy way to easily determine whether it was a human or system that made the change, and joining to the one AuditableIdentity table seems like a clean way to do that? Is there a best practice for this scenario? Is this an appropriate way of approaching the problem - or would you not bother with the common table and just rely on joins (to the two seperate un-related user / token tables) later to determine which user type matches which audit records?

    Read the article

  • EF Forced Concurrency Checks

    - by Imran
    Hi, I have an issue with EF 4.0 that I hope someone can help with. I currently have an entity that I want to update in a last in wins fashion (i.e. ignore concurrency checks and just overwrite whats in the db with what is submitted). It seems Entity Framework not only includes the primary key of the entity in the where clause of the generated sql, but also any foreign key fields. This is annoying as it means that I don't get true last in wins semantics and need to know what value the fk field had before the update or I get a concurrency exception. I am aware that this can be short circuited by including a foreign key field as well as the navigation property on the entity. I would like to avoid this if possible as it's not a very clean solution. I was just wondering if there was any other way to override this behaviour? It seems like more of a bug than a feature. I have no problem with ef doing concurrency checks if I instruct it to do so but not being able to bypass concurrency completely is a bit of a hindrance as there are many valid scenarios where this is not needed

    Read the article

  • Building a formset dynamically

    - by vorpyg
    I initially wrote code to build a form dynamically, based on data from the DB, similar to what I described in my previous SO post. As SO user Daniel Roseman points out, he would use a formset for this, and now I've come to the realization that he must be completely right. :) My approach works, basically, but I can't seem to get validation across the entire form to be working properly (I believe it's possible, but it's getting quite complex, and there has to be a smarter way of doing it = Formsets!). So now my question is: How can I build a formset dynamically? Not in an AJAX way, I want each form's label to be populated with an FK value (team) from the DB. As I have a need for passing parameters to the form, I've used this technique from a previous SO post. With the former approach, my view code is (form code in previous link): def render_form(request): teams = Team.objects.filter(game=game) form_collection = [] for team in teams: f = SuggestionForm(request.POST or None, team=team, user=request.user) form_collection.append(f) Now I want to do something like: def render_form(request): teams = Team.objects.filter(game=game) from django.utils.functional import curry from django.forms.formsets import formset_factory formset = formset_factory(SuggestionForm) for team in teams: formset.form.append(staticmethod(curry(SuggestionForm, request.POST or None, team=team, user=request.user))) But the append bit doesn't work. What's the proper way of doing this? Thanks!

    Read the article

  • SubSonic generated code and always filtering records

    - by cmroanirgo
    Hi, I have a table called "Users" that has a column called "deleted", a boolean indicating that the user is "Deleted" from the system (without actually deleting it, of course). I also have a lot of tables that have a FK to the Users.user_id column. Subsonic generates (very nicely) the code for all the foreign keys in a similar manner: public IQueryable<person> user { get { var repo=user.GetRepo(); return from items in repo.GetAll() where items.user_id == _user_id select items; } } Whilst this is good and all, is there a way to generate the code in such a way to always filter out the "Deleted" users too? In the office here, the only suggestion we can think of is to use a partial class and extend it. This is obviously a pain when there are lots and lots of classes using the User table, not to mention the fact that it's easy to inadvertently use the wrong property (User vs ActiveUser in this example): public IQueryable<User> ActiveUser { get { var repo=User.GetRepo(); return from items in repo.GetAll() where items.user_id == _user_id and items.deleted == 0 select items; } } Any ideas?

    Read the article

  • gridviev add new row problem

    - by Dominating
    My relation is from two tables - table A and table B. B has fk ID pointing to A.ID. In gridview for sourse i have choosen A. When I append new row in A its ok.. But with this action I want to add new row in B too and init it with some values which are copies from row number Row given as argument in PasteCopy private void PasteCopy(int Row) { XPDataTableObject forCopy = gridView1.GetRow(Row) as XPDataTableObject; gridViewEcnMaster.AddNewRow(); XPDataTableObject toCopy = gridView1.GetRow(GridControl.NewItemRowHandle) as XPDataTableObject; SetA(forCopy);// working SetB(ref toCopy, forCopy); XPDataTableObject toCopy1 = gridView1.GetFocusedRow() as XPDataTableObject; XPCollection historyForCopy = toCopy1.GetMemberValue("FK___B__ID") as XPCollection; foreach (XPDataTableObject item in historyForCopy) { MessageBox.Show(item.GetMemberValue("USER").ToString()); } } public void SetB(ref XPDataTableObject toCopy, XPDataTableObject forCopy) { XPCollection historyToCopy = toCopy.GetMemberValue("FK__B__ID") as XPCollection; XPCollection historyForCopy = forCopy.GetMemberValue("FK__B__ID") as XPCollection; XPClassInfo cinfo = session.GetClassInfo(typeof(SPM_ECN_DataSet.BDataTable)); foreach (XPDataTableObject item in historyForCopy) { XPDataTableObject historyRecord = new XPDataTableObject(session, cinfo); historyRecord.SetMemberValue("USER", GetCurWinUser().ToString()); historyRecord.SetMemberValue("ID", forCopy.GetMemberValue("ID"));//if not set == null historyToCopy.Add(historyRecord); } } public void SetA(XPDataTableObject forCopy) { gridView1.SetFocusedRowCellValue("VERSION", 1); } What is wrong with this? why its locking all my application after i do this?

    Read the article

  • Windows Mobile : How to bind dropdown's selectedvalue to a column in table A and the list data to a

    - by Rob
    Hi, I am trying to learn the basics of Windows Mobile development against SQL CE and have come across a basic problem. I have two tables. One called Customers that stores customer info and has an identity column called ID as the primary key. The other table is called Orders which has a column called CustomerID (the FK constraint is present). I have added a DataSet to the project that contains both tables and have autogenerated the edit/view forms. This has produced a text control for the CustomerID column in the Order table for the new/edit form and I deleted it and replaced it with a dropdown list. Then, using the 'Advanced' databinding options (in Properties) I set the datasource of the list to the Customers table setting the value to the ID field and the text to the CustomerName field. I then set the SelectedValue of the list box to the CustomerID field of the Orders dataset. So far so good. When I run the app in the emulator and view the 'New' form for Orders the Customer dropdown is indeed populated with a list of customer names and I can select one and happily create a new order successfully. This is confirmed when I see the order appear in the Orders Grid form. However, when I then click on the order in the grid and then select 'Edit' the order loads but the dropdown always shows the first customer in the list and doesn't seem to bind the SelectedValue to the Orders dataset CustomerID field. Now I am an ASP.NET guy and normally hand craft the DAL and it's binding to the UI so I'm not entirely sure where to look to investigate what is going wrong here as this is all generated code. I am sure it is something very trivial but any pointers would be appreciated. My gut feeling is that the SelectedValue and the Customers.CustomerID values do not match for some reason? Many thanks, Rob.

    Read the article

  • Data Modeling of Entity with Attributes

    - by StackOverflowNewbie
    I'm storing some very basic information "data sources" coming into my application. These data sources can be in the form of a document (e.g. PDF, etc.), audio (e.g. MP3, etc.) or video (e.g. AVI, etc.). Say, for example, I am only interested in the filename of the data source. Thus, I have the following table: DataSource Id (PK) Filename For each data source, I also need to store some of its attributes. Example for a PDF would be "numbe of pages." Example for audio would be "bit rate." Example for video would be "duration." Each DataSource will have different requirements for the attributes that need to be stored. So, I have modeled "data source attribute" this way: DataSourceAttribute Id (PK) DataSourceId (FK) Name Value Thus, I would have records like these: DataSource->Id = 1 DataSource->Filename = 'mydoc.pdf' DataSource->Id = 2 DataSource->Filename = 'mysong.mp3' DataSource->Id = 3 DataSource->Filename = 'myvideo.avi' DataSourceAttribute->Id = 1 DataSourceAttribute->DataSourceId = 1 DataSourceAttribute->Name = 'TotalPages' DataSourceAttribute->Value = '10' DataSourceAttribute->Id = 2 DataSourceAttribute->DataSourceId = 2 DataSourceAttribute->Name = 'BitRate' DataSourceAttribute->Value '16' DataSourceAttribute->Id = 3 DataSourceAttribute->DataSourceId = 3 DataSourceAttribute->Name = 'Duration' DataSourceAttribute->Value = '1:32' My problem is that this doesn't seem to scale. For example, say I need to query for all the PDF documents along with thier total number of pages: Filename, TotalPages 'mydoc.pdf', '10' 'myotherdoc.pdf', '23' ... The JOINs needed to produce the above result is just too costly. How should I address this problem?

    Read the article

  • Convert SQL with Inner AND Outer Join to L2S

    - by Refracted Paladin
    I need to convert the below Sproc to a Linq query. At the very bottom is what I have so far. For reference the fields behind the "splat"(not my sproc) are ImmunizationID int, HAReviewID int, ImmunizationMaintID int, ImmunizationOther varchar(50), ImmunizationDate smalldatetime, ImmunizationReasonID int The first two are PK and FK, respectively. The other two ints are linke to the Maint Table where there description is stored. That is what I am stuck on, the INNER JOIN AND the LEFT OUTER JOIN Thanks, SELECT tblHAReviewImmunizations.*, tblMaintItem.ItemDescription, tblMaintItem2.ItemDescription as Reason FROM dbo.tblHAReviewImmunizations INNER JOIN dbo.tblMaintItem ON dbo.tblHAReviewImmunizations.ImmunizationMaintID = dbo.tblMaintItem.ItemID LEFT OUTER JOIN dbo.tblMaintItem as tblMaintItem2 ON dbo.tblHAReviewImmunizations.ImmunizationReasonID = tblMaintItem2.ItemID WHERE HAReviewID = @haReviewID My attempt so far -- public static DataTable GetImmunizations(int haReviewID) { using (var context = McpDataContext.Create()) { var currentImmunizations = from haReviewImmunization in context.tblHAReviewImmunizations where haReviewImmunization.HAReviewID == haReviewID join maintItem in context.tblMaintItems on haReviewImmunization.ImmunizationReasonID equals maintItem.ItemID into g from maintItem in g.DefaultIfEmpty() let Immunization = GetImmunizationNameByID( haReviewImmunization.ImmunizationMaintID) select new { haReviewImmunization.ImmunizationDate, haReviewImmunization.ImmunizationOther, Immunization, Reason = maintItem == null ? " " : maintItem.ItemDescription }; return currentImmunizations.CopyLinqToDataTable(); } } private static string GetImmunizationNameByID(int? immunizationID) { using (var context = McpDataContext.Create()) { var domainName = from maintItem in context.tblMaintItems where maintItem.ItemID == immunizationID select maintItem.ItemDescription; return domainName.SingleOrDefault(); } }

    Read the article

  • Temporary users table or legitimate users table?

    - by John
    I have a freelance web application that lets users register for events. In my database, I have a t_events_applicants table with the column t_events_applications.user_id with a foreign key constraint linked to the t_users.user_id column. So this means only users who have registered with my web application can register for my web application's events. My client would now like to allow non-registered users, users who do not have an entry in my t_user table, to register for events. These non-registered users only need to provide their name and email address to register for events. Should I create a t_temporary_user table with columns name and email and then remove the t_events_applicants.user_id fk constraint? Or should I add un-registered users to the t_user table and then add a column called t_user.type where type can be 'registered' or 'non-registered'? How do I decide which approach to go with? A lot of times, I hesitate with either approach. I ask myself, "What if at a later time, a temporary user is allowed to become a fully registered user? Then maybe I should have only a t_user table. But then I also don't feel good about storing a lot of temporary users in t_user."

    Read the article

  • mysql subselect alternative

    - by Arnold
    Hi, Lets say I am analyzing how high school sports records affect school attendance. So I have a table in which each row corresponds to a high school basketball game. Each game has an away team id and a home team id (FK to another "team table") and a home score and an away score and a date. I am writing a query that matches attendance with this seasons basketball games. My sample output will be (#_students_missed_class, day_of_game, home_team, away_team, home_team_wins_this_season, away_team_wins_this_season) I now want to add how each team did the previous season to my analysis. Well, I have their previous season stored in the game table but i should be able to accomplish that with a subselect. So in my main select statement I add the subselect: SELECT COUNT(*) FROM game_table WHERE game_table.date BETWEEN 'start of previous season' AND 'end of previous season' AND ( (game_table.home_team = team_table.id AND game_table.home_score > game_table.away_score) OR (game_table.away_team = team_table.id AND game_table.away_score > game_table.home_score)) In this case team-table.id refers to the id of the home_team so I now have all their wins calculated from the previous year. This method of calculation is neither time nor resource intensive. The Explain SQL shows that I have ALL in the Type field and I am not using a Key and the query times out. I'm not sure how I can accomplish a more efficient query with a subselect. It seems proposterously inefficient to have to write 4 of these queries (for home wins, home losses, away wins, away losses). I am sure this could be more lucid. I'll absolutely add color tomorrow if anyone has questions

    Read the article

  • Entity Framework. Updating EntityCollection using disconnected objects via navigation property.

    - by yougotiger
    I have a question, much liket this unanswered one. I'm trying to work with the entity framework, and having a tough time getting my foreign tables to update. I have something basically like this in the DB: Incident (table): -ID -other fields Responses (table): -FK:Incident.ID -other fields And and entities that match: Incident (entity) -ID -Other fields -Responses (EntityCollection of Responses via navigation property) Each Incident can have 0 or more responses. In my Webpage, I have a form to allow the user to enter all the details of an Incident, including a list of responses. I can add everything to the database when a new Incident is created, however I'm having difficulty with editing the Incident. When the page loads for edit, I populate the form and then store the responses in the viewstate. When the user changes the list of responses (adds one, deletes one or edits one). I store this back into the viewstate. Then when the user clicks the save button, I'd like to save the changes to the Incident and the Responses back to the DB. I cannot figure out how to get the responses from the detached viewstate into the Incident object so that they can be updated together. Currently when the user clicks save, I'm getting the Incident to edit from the db, making changes to the Incident's fields and then saving it back to the DB. However I can't figure out how to have the detached list of responses from the viewstate attach to the Incident. I have tried the following without success: Clearning the Incident.Responses collection and adding the ones from the viewstate back in: Incident.Responses.Clear() for each objResponse in Viewstate("Responses") Incident.Responses.add(objResponse) next Creating an EntityCollection from my list and then assiging that to the Incident.Responses Incident.Responses = EntityCollectionFromViewstateList Iterating through the responses in Incident.Response and assigning the corresponding object from viewstate: for each ObjResponse in Incident.Responses objResponse = objCorrespondingModifedResonseFromViewState Next These all fail, I'd like to be able to merge the changes into the Inicdent object so that when the BLL calls SaveChanges on the changes to both the Incident and Responses will happen at the same time. Any suggestions? I keep finding lots of stuff about assigning foreign keys (singular), but I haven't found a great solution for doing a set of entities assigned to another entity in this manner.

    Read the article

  • How can I provide users with the functionality of the DBUnit DatabaseOperation methods from a web in

    - by reckoner
    I am currently updating a java-based web application which allows database developers to create stored procedure regression test suites for database testing. Currently, for test setup, execution and clean-up stages, the user is provided with text boxes where they are able to enter SQL code which is executed by the isql command. I would like to extend the application to use DB Unit’s DatabaseOperation methods to provide more ways to setup the state of the database than just SQL statements. The main reason for using Db Unit rather than just SQL statements is to be able to create and store xml and xls DataSets on a server where they can be associated with their test cases and used for data setup. My question is: How can I provide users with the functionality of the DBUnit DatabaseOperation methods from a web interface? I have considered: Creating a simple programming language and a parser to read some simple syntax involving the DB Unit method names which accept a parameter being the file location to an xml or xls DataSet. I was thinking of allowing the user to register the files they need with the web app which would catalogue them and provide each file with an identifier which could passed as a parameter to the methods in this simple programming language. Creating an XML DTD which provides the user with the ability to specify operations and parameters. If I went this approach, how can I execute the methods and their parameters that I parse from the XML document? Creating a table in the database which stores the method and a FK relation to a catalogued DataSet file, however I don’t think this would be good solution due to the fact that data entry would be tedious. Thanks for your help.

    Read the article

  • MVC 2 - Name Attributes on HTML Input Field when using Parent/Child Entities

    - by Click Ahead
    Hi All, I'm pretty new to MVC 2 using the Entity Framework. I have two tables Company {ID int identity PK,Name nvarchar} and User {ID int identity PK,UserName nvarchar,CompanyID int FK}. A Foreign Key exists between User and Company. I generated my ADO.NET Entity Data Model, a Controller and a view to insert a record. My HTML form has the fields Company and UserName and the idea is when I click save a Company and User is inserted into the database. Sounds straight forward right! My question is as follows: I created a strongly-typed view derived from my 'User' entity. I'm using the the html helper Html.TextBoxFor(model = model.Organisation.Name) but the html name attribute for this input field is 'Organisation.Name'. My problem with this is that the dot throws up all sorts of issues in JQuery, which sees this as a property. If I want to change the name I read that I can use DataAnnotations but because I used the Entity Designer this involves using Buddy Classes. Seems like a bit of overkill just to change the html name attribute on this input field. Am I approaching this the right way or am I missing something here? Thanks for the help !

    Read the article

< Previous Page | 9 10 11 12 13 14 15 16  | Next Page >