C# - LINQ To Entity Framwework Multiple Joins With Multiple Dynamic Search Criteria?
Jul 2, 2010
The gist of the problem is that we have an alumni table (one record per person) and also a couple of other tables (one to many) that have degree info and interest info. In a search screen in our app you can search for criteria that spans all three tables (there are actually more fields and tables than shown in the example below but I am trying to keep it simple).
The code below works (properly returns people without degrees for example) but still feels a little clunky or over-engineered to me. Are there easier ways to do this? NOTE: I have been through quite a few iterations/approaches to making the correct data be returned.
[code]....
View 1 Replies
Similar Messages:
Jan 28, 2011
I have some problems trying to query my database. The problem is that I'm not sure how to multiple join tables in my database.
tables to make it easier:
[code]....
What I'm supposed to do is to find all the teachers (predavac) who were teachers on the specific activity (aktivnost) and who had specific attendee (polaznik). The problem is I'm not sure how to do multiple joins on this one.
View 1 Replies
Nov 18, 2010
im trying to write a query. for my ui ,i have 3 text boxes for firstname,flightno,sequencenumber.
i input search value on particular textbox it has to be searched on particular column of my db in a single stored procedure.
im using this procedure but it retrives only one column at atime. so like this i need to write three procedures.
but i have only one GO button.
ALTER PROCEDURE [dbo].[spp_searchUsers3]
@lastname nvarchar(50),
@Value varchar(50)
AS
DECLARE @SQL nvarchar(500)
SET @SQL = 'SELECT firstname,flightnumber,lastname,status FROM tbl_pregister WHERE '
+ @lastname + ' LIKE ''%' + @Value + '%'''
View 4 Replies
Jul 17, 2010
search form!Have no idea how to do it.Hope the example says much about how it should operate!Profile search where the result will come out in a list view.theusers should be able to filter between firstname, lastname, age, gender.right now I have this!Search page
[Code]....
Search result page
[Code]....
[Code]....
View 11 Replies
Dec 15, 2010
I am selecting some products from database and would like to show them in client's grid using WCF. Problem is I don't know how to pass selected collection to the client since my method can't return that data type.
My method:
public class Service1 : IService1
{
public ProductData GetData(int value)
{
using( NorthwindEntities NWEntities = new NorthwindEntities()){
[Code]....
View 2 Replies
Jan 24, 2011
I'm a newbie to this so bear with me. From what I've read online LINQ to Entity should see the relationships without having to specify the joins between multiple tables. I have a relationship that goes across 4 tables Employee, EmployeeDepartmentLink, EmployeeProjectLink, and Project. The idea is an employee can be in multiple departments and work on multiple projects with it being specified which department the employee is in for that project.
This is a C# MVC3 program connecting to a SQL database using VS 2010 Express.
I have no problem with running this query to find employees on a project:
[Code]....
Tring to do the reverse, finding projects that an employee worked on results in an error:
[Code]....
Error message: The specified type member 'EmployeeDepartmentLinks' is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported. So I have 2 questions,
1) Why would it work in one direction and not the other? I've played around with it for a couple days with the same results.
2) Does it matter that my primary key and foreign keys are not named the same since all the relationships are connected in SQL? Ex: in Employee (EmployeePK)--(EmployeeFK) in EmployeeDepartmentLink Trying different stuff in LINQPad I was able to get the 2nd query to work if I specified all the joins which I thought was not neccesary with LINQ to Entity. I converted an SQL query that I made on the server into a LINQ query below which works.
View 5 Replies
May 7, 2015
I've created a filter textbox for searching my data in gridview..
ex: i've 3 columns in gridview : ID, NAME, DATE
I ask, how to create a dynamic search for 3 columns in gridview using a textbox?
without writing a query repeatedly :(ID like '%" + search + "%') OR (NAME like '%" + search + "%') OR (DATE like '%" + search + "%')
protected void btnCariConnStrSubmit_Click(object sender, EventArgs e) {
string search = ((TextBox)GridView1.HeaderRow.FindControl("txtCariConnStr")).Text;
string sql = "select * from report where (ID like '%" + search + "%') OR (NAME like '%" + search + "%') OR (DATE like '%" + search + "%') ";
reader = mda.GetData(sql, connStr).CreateDataReader();
if (reader.Read()) { dt = mda.GetData(sql, connStr).Tables[0]; BindGridView(dt); lblRecordNotFound.Visible = false; }
else { Bindemptydt(); lblRecordNotFound.Visible = true; }
((TextBox)GridView1.HeaderRow.FindControl("txtCariConnStr")).Text = search;
}
View 1 Replies
Mar 22, 2010
I have one question regarding how to make the below mentioned type of query more optimized so that mine query perfomace can be increased.
Select a.name1,a.address1,b.field3,c.field4,d.field6,e.field7
from a
inner join b on a.id=b.id
inner join c on c.id=b.id
inner join d on d.id=c.id
iner join e on e.id=d.id
union all
Select a1.name1,a1.address1,b1.field3,c.field4,d.field6,e.field7
from a1
inner join b1 on a1.id=b1.id
inner join c on c.id=b1.id
inner join d on d.id=c.id
iner join e on e.id=d.id
union all
Select a2.name1,a2.address1,b2.field3,c.field4,d.field6,e.field7
from a2
inner join b2 on a2.id=b2.id
inner join c on c.id=b2.id
inner join d on d.id=c.id
iner join e on e.id=d.id
All the above three select query at last using the same inner join condition, means last two inner join condition are the same for all the select query.
Is there any way so that this query can be optimized?
View 2 Replies
Jul 22, 2013
I created 3 product table . A,B and c.
I show product of table in different gridview.
Now I am using one search box. but how to search product name with image in one query all of three table....
Simple how to search product from multiple table and show result...
View 1 Replies
Dec 16, 2012
I want to search data from three text boxes how can i write code in one button click ??? This if else is not gud formed
protected void Button2_Click(object sender, EventArgs e) {
if (TextBox2.Text == "" || TextBox3.Text =="") {
DateTime dt = Convert.ToDateTime(TextBox1.Text);
SqlCommand cmd = new SqlCommand("SELECT * FROM Transactions where report_type = @report_type and dateadd(dd, datediff(dd,0, [R_date]), 0) = @R_date ");
[Code]...
View 1 Replies
Oct 30, 2012
how to give a multiple inner joins to the single table
View 1 Replies
Nov 15, 2010
One of my peer wrote a query based on multiple tables using joins. One of the table is in a different database The query was taking much time
1. Create an SP
2. Create a temp table and copy all records from the external db
3. Avoid using Left Join as much as possible and use Inner Join
4. Create and use indexes
5. Remove tables/columns that are not necessary
In this scenario, I would like to suggest to use Covering Index, but how can it be created for multiple tables and a temp table?
View 3 Replies
Dec 29, 2010
I am working on a project for a market research company that needs to select and have it displayed to my gridview. I need a select statement that will randomly put on my gridview the following:
Recruitment Goal 21 people and out of those people 10 people have to be male, 11 people female, 9 of them white, 9 of them black, 2 of them hispanic. Is there a way I could do that? I was thinking of doing a stored procedure and doing something like
Select TOP 10 * from Canidates where sex = 'Male' order by newid() Into #tmp
Select TOP 11 * from Canidates where sex = 'Female' order by newid() Into #tmp
Etc... and then just selecting from the Temp Table.
View 10 Replies
Aug 4, 2010
I have an application that needs to render a page that will have multiple Radio Button Groups as well as multiple CheckBoxes. The desired layout is determined by a database table.
table structure:
PackageID uniqueidentifier
PackageName string
ItemName string
RadioGroupName string
ViewControlName string
This table defines a "Package". The "Package" can contain many different "Items" that require different controls used in the View. The "RadioGroupName" field is used to mark which RadioButtons should be grouped together. The "ViewControl" field marks which control should be used on the View to display the field. The query in my repository will return a result set such as
1 / "First Package" / "Item1" / "First Group" / "RadioButton"
2 / "First Package" / "Item2" / "First Group" / "RadioButton"
3 / "First Package" / "Item3" / "First Group" / "RadioButton"
4 / "First Package" / "Item4" / null / "CheckBox"
5 / "First Package" / "Item5" / null / "CheckBox"
6 / "First Package" / "Item6" / "Second Group" / "RadioButton"
7 / "First Package" / "Item7" / "Second Group" / "RadioButton"
8 / "First Package" / "Item8" / "Second Group" / "RadioButton"
Given this result set, I need to render the view as follows:
A RadioButton group with 3 options (Item1, Item2, Item3)
A CheckBox (Item4)
A CheckBox (Item5)
A RadioButton group with 3 options (Item6, Item7, Item8)
I have read that it is possible to use "if" conditions and looping structures inside the View. I have also read that this is a bad practice. Another issue I see is knowing which Item has been selected from each RadioButton group when I hit the Controller POST function. Previously I have built a page that has a single RadioButton group. My ViewModel was as follows:
[Code].........................
View 1 Replies
Apr 15, 2010
I want to select data from a table where the user can search by 3 options; date, keyword, and type. The date will always be either today or a user chosen date. The keyword can be null or something the user inputs. The type will be chosen from a drop down and can be all or a specific category. I know how to search the date, but the other two create complications. I have created a stored procedure trying to figure this out:
[Code]....
Is there a way to say if the keyword is null then don't use it as a search criteria. If that is possible then type can use that same logic I suppose.
View 6 Replies
Dec 24, 2010
We would like to perform something like this
string strCondition = "FirstName=='abc'"
from p in People.Where(strCondition) select p
In our architecture we are usign both Linq-Sql as well Linq-Entity. So please give some thoughts wehter it is possible or not and is there any way to perform this?
View 2 Replies
Feb 8, 2011
i have the following controls:
[Code]....
And the onclick method:
[Code]....
The Search.aspx has a SqlDataSource that get that querystring and search on 3 DBs for just 1 word. I was wondering how i could implement if i want to search for multiple words on that Textbox txtSearch. Could i use the SqlDataSource for that or should i use LINQ or another component ?
View 4 Replies
Sep 29, 2010
getting data from multiple Entities models into an MVC controller. Most of the examples I have seen for using EF in an MVC2 app only use a single entitiy.
I have just started using MVC2 in C# using the Entity Framework models (CIOps.model) created from an SQL database. I can create the controller and views using single tables of the model in MVC2, but I just cannot get my head around how to get data from multiple entity tables into the controller (similar to joins in T-SQL). I have included an example below of the controller code that works with a single entity table, tbl_tours (tbl_tour in DB).
Could someone please illustrate how this code would be changed to include additional columns from FK tables in addition to tbl_tours columns. E.g. the clients name from the tbl_clients, the coordinators name from the tbl_employees, and costs from tbl_costs entities? Is it possible to do this directly using the EF model entities/classes that are already created and not use LINQ, POCO, Repositories, etc.? The FK relationships are already in the EF models. I have included the whole controller code, but I just need a few examples of how to join the multiple entities, not rewrite every CRUD function function in the controller. I think this will get me over the hump in using EF in an MVC2 App. Also ignore the fact I am using the home controller, this will change in the application.
[Code]....
View 21 Replies
Apr 4, 2011
It is about ASP.NET MVC3. I have a page with at the top some search criteria and at the bottom the resulting data. The user can type some criteria and use a submit button to retieve data. In my controller, I have an ActionResult function for managing these criteria and return to the same page with a ViewModel class filled.
The problem: the user can click on a line in the resulting table for viewing a detail page. On the detail page, he can navigate to an edit page for editing data. On this page (edit data) I would like to able the user to go back to the search result page (in fact: navigate back two times). What is the best way to proceed? If I "simply" use an ActionLink (without posting data) to my search result page, it will simply display an empty result page with empty search criteria. Maybe I need to keep my search criteria in a session variable? I don't like this kind of thing...
View 1 Replies
May 7, 2015
I have storedprocedure which returns four or more dataset!
example here
How load and display all data in Default.aspx....
dataset 1
............................................
dataset 2
............................................
dataset 3
............................................
dataset 4
............................................
View 1 Replies
Dec 4, 2010
I have this query for getting data through Entity Framework, which works today. Thing is, i want to create the query dynamically, i.e build it up in blocks, but i can't figure out how exactly to do it. I believe if i can somehow save one of the values that i retrieve in the beginning i can do it, but now i retrieve it twice (probably a bit slow as well? Unless the compiler fixes it before quering). Makes sense? Here is the LINQ:
[code]....
I.e based on if various variables have values.
View 1 Replies
Jan 12, 2011
I have two text boxes for the user to enter UserName & First Name, both these fields are optional and not mandatory to fill.
once the user presses the Search button, i execute the following query to fetch matching records.
[Code]....
The problem is, in cases where User leaves both the textbox or one of the textbox empty/blank, in that case that particular field should be removed from where clause.
More like if something is entered then search for that particular record otherwise search for all the records.
View 2 Replies
Aug 3, 2010
I am using dynamic data entities linq to sql project. For my test project I have one table, with 10 columns and a single primary key for example. Almost all the columns are varchars.I can get the basic project up and running fine - update, delete, insert etc.ince it has no foreign keys, there are no search filters rendered. I was wondering if there was an easy way to generate a set of filters for the columns for this table. So a First name and last name search box. Is there a way to generate these filters for chosen columns and is there a way to generate these for all the columns
for example, above each of the columns in the grid there might be a text box ( I am not too fussed where the text boxes are rendered as such). Each of the text boxes will act as a filter for that column (doing a SQL 'like')
View 1 Replies
Nov 22, 2010
Is it possible to do an optional join as follows?:
private void OptionalJoin(string phrase)
{
from t in db.Table
// (if phrase != string.Empty then) join t2 in db.Table2 on t.Id equals t2.Id
select t
}
Although I'm aware that I can copy/paste this and move the conditional logic outside the query, the query is ~200 lines and there are 4 different optional joins I would like to incorporate, so it would get messy and be difficult to maintain. I'm looking for a clean, streamlined way to do this.
View 2 Replies
Mar 10, 2011
I have two tables.[Table.Game] Columns are "PK_id" "username" and "couponID" [Table.Coupons] Columns are "PK_id" "CouponID" and "Points" The two columns "CouponID" are associated with eachother. Let say i have two rows with the user "harry" in [Table.Game] this person has two different couponID. In [Table.Coupons] this user "harry" has "CouponID" 1 and 2. Column "Points" have 10 and 20. To the question how do u sum this two different point values that have different "CouponIDs". This does work if i have only one "CouponId". But not when the user has 2 different CouponIDs. Values is 0
var points = (from p in linq.Coupons
join g in linq.games on p.couponID equals g.couponID
where g.username == username && g.couponID == p.couponID
select (int)p.win).Sum();
View 2 Replies
