DataSource Controls :: Retrieving Data From Multiple Tables?
Aug 17, 2010
I have hard time trying to find the solution to retrieve data from multiple tables in one database.
table Kategorije has fields: idKategorija, naziv, opis table Clanak has fields: idClanak, idKategorija, naslov, autor,...
Kategorije.idKategorijais joined with Clanak.idKategorija, but that isn't the solution because I want my web site to show the Kategorije.naziv instead of Kategorije.idKategorija. This is the code I'm currently using to get idKategorije shown on my web site:
I'm quite new to ASP.NET and i was wondering if someone could answer some of my questions.1. What is the difference between a DataTable and an Array? Is the DataTable a serverside control? Is it exposed to the user?2. Does the reader retrieve the column names? If so- how can I capture them? Are they the first row?2. Is it possible to populate an Array using the following sort of code, and if so- how?:
SqlCommand tableCommand = new SqlCommand(); SqlConnection tableConnection = new SqlConnection(); tableCommand.Connection = tableConnection;
I am writting a directory website that advertises fitness classes. These classes are listed by Class Type, and Geographical Area. Each Class Type can satisfy one or more of four Fitness Goals such as Loose Weight etc...
I have a table for Classes (classid, classname, classdesc, classtypeid, geoareaid) I have a table for geographic areas (geoareaid, geoarea) And I have a table for ClassTypes (classtypeid, classtypename, classtypedesc)
Which obviously links geographic area via the classes.geoareaid as a forgien key and classtypes by classes.classtypeid as a forgien key.
I can list all classes by type and also by geo area no problem, the problem arrises when I then also want to filter by goal.
The Goals Table (goalid, goal, goaldesc) is linked to the classtypes table via another table classtypes_goals (classtypeid, goalid) as each classtype can satisfy any of the 4 goals.
I am using a DataSet to fetch the data from a Stored Procedure in the SQL Database but because the classtypes can be linked to multiple goals I am getting duplication in my list depending on how many goals a classtype satisfies.
All I need in my data list is class name, class type and area I don't even need to display the goal I just want a drop down above the table that will filter the list and show only classes of classtype that satisfy the goal chosen.
After creating a dataset, which has CRUD statements generated two or more tables, which Data Control should I use that will allow me to insert data into fields into 2 or more tables from a single web form. I'm trying to create a web form that will allow the user to input student information, such as general information, medical information, etc.
I have a sproc that will insert a new record into Table1. Next I need to Insert into another table the scope_identity of the inserted record. How do I incorporate the scope_identity value as the insert parameter in the second insert statement?
I've got a TextBox to capture the value of "Name" in Table A.
Ive got a CheckBoxList that displays all the pre-determined values of Table B.
When the user selects an item from the CheckBoxList i want to populate Table C with the value of the selected item from the CheckBoxList and the cooresponding ID associated with the user name for that person's entry.
I have a dataset with 3 tables that are inner joined. Thsi dataset is connected to an object datasource which is connected to a gridview. So at runtime it displays data from the database. The problem is when I click on a save button to add information to the database it throughs me an error saying Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints. But if i have two tables in my dataset it works 100%. But the problem i need that 3 tables in order to pull the required information. And if i populate the gridview using code to select the information from the database and insert information it also works 100%.
I am using ASP.NET 2.0, C# and Sql Server 2005.I have 2 tables retruned by the stored procedure to the application. I am returning an Array from my datalayer to my bussiness layer and then to my UI layer.I have added the first table into the array and passing it to the UI layer. This is my current code:
How to pass the second table details to the same array, NameArrayKeyEntity .
I have a dataset that comprises of multiple tables (about 20) linked together with constraints to reflect the relational database. My question(s):
1) Will having multiple tables affect performance? I'm asking this as there are often times I would not need to get data for all the tables, but only for specific tables.
2) If it does affect performance, would breaking up the tables into their own datasets be the best solution. It seems to me that by doing that, you would lose the ability to apply constraints among tables and tables that might exist in multiple datasets will be subjected to replication.
I would like to have everything in one dataset as I get a view of the related tables and their relationships and also because the Fill method allow me to fill tables, maintaining the hierarchy of the data, but performance is still a key factor.
I am confused about why I would need to wrap the DataContext's SubmitChanges within a transactionScope when modifying multiple tables. I was under the impression that the DataContext would track these changes and would therefore create its own transaction if need be.
In other words, if a change was made to update table A, B and C or if I made changes to 10 out of 20 items in a collection of rows, that the datacontext would track these changes and create its own transaction. If that is correct then why have I seen examples that wrapped these types of updates in a TransactionScope?
I have multiple user controls on the page that are used primarily for data entry purposes. When a product is loaded, I need to load the product data into all those user controls and retrieve data when I need to save the product. The user controls are not visible to the user directly, instead user would click on a link and the user control will open up in a modal popup.
Currently the way I'm doing this is, I've loaded all the user controls on the page in separate div controls, and showing the modal popup when the link is clicked. I'm sure loading all the user controls on the page is not a good idea. Is there a better way to handle this? I think we can show the markup using JSON with jQuery - but how can I load and retrieve the data using that?
but i have a problem to retrieve value from the database in the textbox using 3-tier application. ]
in the App_data i have following folder.
1> employeeBAL in this i have 1class file called empbasicinfoBLL.cs
2> employeeDAL in this i have test_data.xsd
in the basic details folder i have one page Basic information(employee basic info) in this i want that when user will log in the site [using username and password] after successful login when user will click on the Basic information then he will able to see his [name, employee no, first name, last name] etc on the page [i don't want to use grid-view to retrieve the details becoz i am using the table in this i am using Lable and Textbox for each] and this data should come from the EmployeeBAL.
I'm currently working on a FOREX Live Trading project that I'm implementing.
I already have a database that stores the CURRENCY PAIR, BUY/SELL, PRICE AND QTY.
But I have a huge problem.
Scenario that is:
A person BUYS EUR/USD at a PRICE of 1.29900 @ quantity 100,000. (This will be recorded in the database table)
Then he BUYS EUR/USD at a PRICE of 1.29950 @ quantity 100,000. (This will then be recorded in the database also)
Then he decides to SELL his EUR/USD at a PRICE of 1.31000 @ quantity 200,000 all out. (How can I check from the database if he previously had make a transaction of BUY/SELL, so that I can do my necessary calculations for the P/L Statement)