Relationship Between Data Tables?
May 21, 2009
I am using VS2008 Standard, Access 2007 and VB.net. I have an Access db with a Membership table, a DuesPayment table and a table linking the two together.
[code]....
1) In VS I have a single form (frmMembership). I used the Data Sources window to create a single datasource containing the tables tblMembers, tblDuesPayment and lktblMemToPay. from the 'Data Sources' window I drug tblMembers, as text boxes, to the form. I drug tblDuesPayment to the form as a DataGridView.
I right-clicked 'dsMembership...Edit in Dataset Designer' and checked that the relations between the three tables was as shown above. I left all other settings as they were created by VS.When I execute the app I get the member information as expected and can use the TblMembersBindingNavigator to step through the members. The DataGridView, instead of showing dues payment information for the member showing on the form, shows ALL of the dues information for ALL members does not exhibit any relationship between tblMembers and tblDuesPayment.
2)I also tried creating a dataset for tblMembers only. Then I used 'dsMembership.Edit in DatasetDesigner' window to create a TableAdapter for tblDuesPayment and lktblMemToPay. I got the same results.
3) I tried various other combinations, like creating TableAdaptors for tblMembers and a TableAdaptor for a combination of lktblMemToPay & tblDuesPayment.
View 2 Replies
ADVERTISEMENT
May 17, 2012
I use Visual Basic 2008 Database is Mysql Three tables:
[Code]...
View 2 Replies
Dec 15, 2011
How do we create relation ships between tables using a sql query?im using MS Access and VB.net.
View 2 Replies
Sep 8, 2009
I'm using a dataset class written by others who have defined the foreign key relationships between tables using the tools in the schema diagram. I'm binding the dataclass to a windows form. I'm running into an issue where I have an existing header record and I'm trying to insert data into a child table via a grid programmatically. The child table contains all keys for data. As the grid is bound to a binding source, I'm simply adding rows directly to the grid programmatically.
When I attempt to save the data, I get the error ForeignKeyConstraint FX_Activity_UserRoleActivity Requires Child Key Values (4) to exist in the parent table. The value (4) is one of the foreign key values and it does exist in the parent table. The error occurs when I tell the bindingsource associated to the child table on the form to EndEdit. Looking at the XSD file for the dataset, both foreign keys are set up for 'Both Foreign and Key Constraint' with Cascade set for both update rule and delete rule. Accept/Reject rule is set to none.
Running a SQL trace, I confirmed that SQL Server is not generating the error, so it is occurring on the client application somewhere. First what does the error actually mean? Second, does the configuration of the foreign key relationship in the dataset's XSD file have anything to do with it? If so how should the foreign keys be set up between the tables? If it isn't how would you go about troubleshooting this issue as stepping through the code ends with the .EndEdit call to the binding source.
View 3 Replies
May 8, 2010
StudentId is a foreign key in StudentSubject,What I want know is how do I illustrate the relationship between the two tables is many to one
StudentSubject
StudentID Subject
148 Art
148 History Of Art
145 English
145 Poetry
128 Chemistry
128 Physics
128 Biology
123 Math
StudentLocation
Student RoomNumber
123 1a
145 3b
148 4c
128 2a
View 1 Replies
Jun 9, 2011
I am trying to input value to AppSchedNumber into my AppInfo table which is the primary key of my AppExamSchedule (auto inrement). The problem is I can't insert on my AppInfo because my AppSchedNumber on my AppExamSchedule should be the same.
View 1 Replies
Mar 15, 2012
How would I connect different tables with each other in vbnet2008 which ive connected by the database wizard? Also I want to connect this table for the search purpose. I filter it by Name which is in my personal_informationtbl so the rest of the table must show the related information about the Name that I've searched. So meaning if I just search by name it shows related information from the records not just from the personal_informationtbl but fill the other tables with the related information.
View 2 Replies
Jul 2, 2010
I'm going to describe this as simple as possible, and it a typical setup for a database...
I have 1 DataSet, 2 DataGridViews (DGV), and 2 BindingSources (BS).
The DataSet has 2 tables and 1 Relationship (FK).
Table 1 is a employee table
Table 2 is timeclock data.
Both tables contain a column: EmployeeId
FK is linked to EmployeeId of both tables.
DGV1 has it's datasource=BS1
BS1 has it's datasource=DataSet and it's DataMember=Table 1.
Thus DGV1 shows Table 1.
DGV2 has it's datasource=BS2
BS2 has it's datasource=BS1 and it's DataMember=FK
Thus DGV2 shows Table 2 filtered by what's selected in DGV1.
Now when I use the mouse or keyboard to select a cell in DGV1, the relationship causes DGV2 to update to only show data from Table 2 where the EmployeeId row equals that from the selection in Table 1. With me so far?
Well all that works great. But what if I need to programmatically select a row in Table 1 to cause Table 2 to update? I've tried everything I can think of, but Table 2 NEVER updates when I attempt to programmatically select a row or cell in Table 1.
View 3 Replies
Feb 3, 2010
Basically, I am trying to write a LINQ to Objects statement where the relationship is a grandparent, parent, child relationship. (You could also call it a Master Detail relationship.)
Dim coverages As New List(Of Coverage)
Dim coverage As Coverage
For Each rl In oClaimsPolicy.RiskLocations
[code].....
View 1 Replies
Sep 23, 2010
I'm using VS2008 with SQL Express 2010. I've a one to many relationship and a form with these two tables on. I'm using the BindingNavigator toolbar and when I press the + button, a new record appears. However, I have to press the save button and save the parent data (which is in Details view) before I can add any data to the child table (which is in a DataGridView). Once I've clicked save, then I can add child data no problem, then I click save again and all my data is saved.
Is there any way to save all the data at once? If not what is the best practice for telling the user when to save? Should I make the child data grids invisible until the user clicks save?
View 10 Replies
Jul 25, 2012
I am using VS2008 and SQLite. I have created a database and several tables and am attempting to populate the tables with data from arrays.
The following code (example) works fine but stops after it inserts 30 to 50 records. I am running the VB code in debug mode and when it stops, I press pause to see where it is. It stops on "SQLcommand.ExecuteNonQuery()" and when I press continue (F5) it will insert another 30 to 50 records.
I do not get an error message. Is this a timeout issue? How do I keep the loop running to the end of the array?
Following is example code.
Dim
SQLconnect As New SQLite.SQLiteConnection()
Dim SQLcommand As SQLiteCommand
CODE:.....................
View 4 Replies
Sep 28, 2009
I would like to know the best, or standard, way to accomplish real-time client updates in a small multi-user application using an access data table as a data source.Specifically, this application will be used by 3-4 people. It uses a datatable which is filled on form load and bound to a datagrid at design time. The datatable is stored on a shared drive. The data table on the shared drive is updated in two ways:
1) Users can update the datagrid which then updates the datatable on the shared drive via the data adapter's Update method.
2) A server application does some work on some text files, periodically updating the data table.
I need the clients to reflect the changes to the data table on the shared drive as closely to real-time as possible. I know that the data table stored in memory on the client is disconnected from the data table on the shared drive, so I must query again to get the updates.
1) Is there an alternvative model I can use which is connected, and which will automatically reflect the updates in the data table on the shared drive?
2) If not, what is the best way to check for changes in the data table (so I can know when to call the data adapter fill method)? I am planning to poll the drive for a change to the .mdb file, raise an event and then fill the data adapter when the event is triggered. I am using this method successfully now to check for changes to a text file in another application, and I know how to implement it?
View 1 Replies
Sep 28, 2009
I would like to know the best, or standard, way to accomplish real-time client updates in a small multi-user application using an access data table as a data source.
Specifically, this application will be used by 3-4 people. It uses a datatable which is filled on form load and bound to a datagrid at design time. The datatable is stored on a shared drive. The data table on the shared drive is updated in two ways:
1) Users can update the datagrid which then updates the datatable on the shared drive via the data adapter's Update method.
2) A server application does some work on some text files, periodically updating the data table.
I need the clients to reflect the changes to the data table on the shared drive as closely to real-time as possible. I know that the data table stored in memory on the client is disconnected from the data table on the shared drive, so I must query again to get the updates.
I have two questions:
1) Is there an alternvative model I can use which is connected, and which will automatically reflect the updates in the data table on the shared drive?
2) If not, what is the best way to check for changes in the data table (so I can know when to call the data adapter fill method)? I am planning to poll the drive for a change to the .mdb file, raise an event and then fill the data adapter when the event is triggered. I am using this method successfully now to check for changes to a text file in another application, and I know how to implement it
View 5 Replies
Jul 27, 2009
I have two data tables within my data set that are loaded onto my form on form_load using statements written in code (not the designer. When I change a value for the first table via a text box the change is made to the data set. But when I try the same for the second table, the change doesn't remain in the data set when I switch to a different company and come back. I query the second table using the primary key of the first table but no code is needed when I change the values for the first table so I don't understand why the same doesn't work for the second when I change a value via a data-bound text box....
Here is my code that initially binds the data:
'This is used to read our data from the data base
Public Sub Read_Data_SQL()
Call Clear_Bindings()
[CODE]...
Here is the code I call when the selected index of my company combo box changes to have the second table reflect that of the first:
'This sub populates any information contained in the Contact2 table
Private Sub Update_Contact_2()
Dim Company As String = cmbCompany.Text.Replace("'", "''")
[CODE]...
View 1 Replies
Dec 5, 2011
i am trying to join 2 tables together and display them in a list view. i have this code so far
[Code]....
View 1 Replies
Jan 25, 2011
if it affects the run time of a program if I were to have multiple data tables as opposed to one data table with all my data in it? I am trying to minimize datagrids and just use code to access table data, in hopes that it will speed up my program. But I am ignorant if multiple tables vs 1 main table will make a difference because there will still be the same amount of overall data present in my program one way or the other....?
View 3 Replies
May 25, 2012
I have been trying to find and/or think up a way for data to automatically update a data table.I have a log that shows all the customers that came in today with various information. There could be twenty or thirty employees adding to this log or updating or doing things with that customer. This information is in a Data Table on a ASPX page in Visual Studio 2010 that the code is binded in the aspx.vb page that is calling a page in my APP_CODE database file that calls a query in my Database to get the information.My question is could someones actions on a different computer make my computer refresh or to re-bind that data.I have thought of some kind of timer/counter maybe that looks to see if the count of the log is different.
View 2 Replies
Dec 1, 2010
I am about to commence a little project whereby using a forms based application to visualise temperature in a building over a day. I am using data loggers placed strategically around the building (these record temperature and time of the read). I am planning to use a picturebox with the buildings floor plan within it and on using a scrollbar (using time as the metric) scroll through the day with temperature being represented by the size of the graphics on top of the floorplan (these represent the location i placed the data loggers around the building).
I have already built a tool to digitise the location of the loggers on the floor plan (saves the data loggers id ref and x y coordinates in the picturebox back to an access datatable).I am planning to use loops on scoll to draw and resize the graphics in another picturebox. The data loggers could be many (up to 30 or more) hence i am concerned this might grind to a halt or become so staggered that it will cease to be useful.The question i would like to ask is is this the most efficient way of doing this or am i going down a dead end.
View 4 Replies
Oct 2, 2009
i wanted to add data from a single form in vb to two tables in access but an error appears saying that the field customer_ID down to Contact_Number doesnt belong to the table record, though it really doesnt belong to that table.. but i already indicated the table for the customer_ID down to Contact_Number, which is Customer, in my sql statement...
Public Class Refill
Dim connect As New OleDb.OleDbConnection
Dim sql As String
[Code].....
View 7 Replies
May 16, 2010
I'm trying to develop a windows application, I'm using VB.NET(Visual Studio 2005) and MySql database.
View 2 Replies
Mar 27, 2010
this is the code i am using to print the contents of my datatable:
Private Sub PrintDocument1_PrintPage(ByVal sender As Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs) Handles PrintDocument1.PrintPage
Dim xPos As Single = 120
Dim yPos As Single = 120
Dim i As Integer = 0
[Code]...
View 1 Replies
Oct 3, 2009
[Code] what i really want is to add another table to my database with different fields with my first table and have my form in vb input data to the two tables. i already tried it but i always have errors. what should i add to my code?
View 2 Replies
Aug 11, 2009
I have 2 DataTables in vb.net. Each is populated from it's own stored procedure. Table A contains a project number in the first column. Table B also contains the project number in the first column. Table A could have many records that have the same project number, but Table B will always have just one record in it per project number. I would like to append the data from Table B to every matching record in Table A. How would I do this?
[Code]...
View 2 Replies
May 6, 2012
I am making a survey-application in winforms that is connected to a MySQL database. Now I want to show the alternatives of a question, and how many answered each question. I have a table for alternatives called tblAlt and a table for answers from users called tblAnswers.
There are only 5 alternatives for each question. Is there a way to get each alternative, and how many answered each of them with one query?
This is what I made so far, but this is definitely wrong:
SELECT tblAlt.altText, Count(tblAnswers.answerID)
FROM tblAlt, tblAnswers
WHERE tblAlt.questionID = " & CInt(questionID) & "
[Code]....
View 2 Replies
Apr 1, 2009
How can I save data in the textbox to two different tables? I have it bound to tableA to display data and I want to save that data to tableB and tableC when I click save.
View 2 Replies
Nov 19, 2011
I am engaging to build my first project with a database connection and have a question before I go any further:In MS Access when you create a form you have the option to put a subform in and link the data so that each time the main record changes that sub data changes too.My Database and table are complete and ready to go. There are perfectly normalised as well.How can a similar procedure be achieved in VB.Net ?
View 5 Replies
Jan 18, 2009
Does this work the way I think it should?
Private _adapter As New SqlDataAdapter("Select CaseId, CaseNum, DateLoaded, Status1, DateDiff(mm,DateLoaded,GetDate()) as mm From Case_T" _
& ";Select CF.CaseId, CFV.VendorId, CFV.DueDate From CaseFileVendor_T CFV Left Join CaseFile_T CF on CF.FileId=CFV.FileId" _[code]....
View 3 Replies
Jun 12, 2009
hello everyone, i m using treeview control in vb .net . How do we usee a recursive function to add data at different levels from different tables in a database.
View 2 Replies
Mar 20, 2010
This is a winform and I'm using mysql as a database, here is my code:I'm trying to add data into multiple tables.[code]Index and length must refer to a location within the string. Parameter name: length
View 2 Replies
May 12, 2009
I am used to creating a data set with data from one table, for instance:
[Code].....
Now I am needing to add a second table. For instance, my second table "EQUIPMENT" has a field called "DESCRIPTION" that I would like to add to my dataset. The "WORKORDER" table has a field called "EQNUM" which is what the "EQUIPMENT" table uses as the primary key. how to combine these into one dataset?
View 8 Replies
