LinqToSql Contains On Multi-column Primary Key From In-memory List Containing Primary Keys
Aug 23, 2011
On a client i have an anonymous list containing a multi-column primary key previously selected from the DB.Then i need to select all the records from the DB that equals the primary key list i have stored in the memory.[code]
SELECT T.TABLE_NAME as TableName, T.CONSTRAINT_NAME as CONSTRAINT_NAME, K.COLUMN_NAME as FieldName, K.ORDINAL_POSITION FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS T INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE K ON T.CONSTRAINT_NAME = K.CONSTRAINT_NAME WHERE T.CONSTRAINT_TYPE = 'PRIMARY KEY' AND T.TABLE_NAME = 'mytable' ORDER BY T.TABLE_NAME, K.ORDINAL_POSITION
Query for getting pk of a table. When I Run this query to fill dataset from dataadapter it does not return any value while it returns a row when executed from sql server. Fill method is called correctly as it is working from past 8 months and no problem is yet is there any special property of dataadapter. I also used to put above query in a sp and when try to execute that sp the result was sq not found.
EDIT: was a design issueI am undergoing a computing project for Alevel computing.The project consists of a 6 tabled Microsoft access database. I am using vb.net to code the application for a student tracking system.My ERD is below:My problem: How to insert a new compound Primary key into a existing table?If I increment StudID and CourseID in tblContact then I need to increment them in tblStudentCourse which leads to records not pointing to the right directions..For enforcing the relationships I am using the .relations with the dataset.
anyone know how sql pick a random number of primary keys, I know get max number and call a random number work but what if there a missing numbers like 1,2,4,6,7 so max 5 and random will missing 6 and 7 also there a error if 3 and 5 come up.
i have a project where I need to concatenate strings from 4 different tables based on a sequence of numbers. I created a 5th table that holds the number sequence and dictates in what order the strings get appended. I have created primary keys on the tables, but 3 of the tables are composite primary keys. I have written up to where I start referencing the primary keys, but am not sure how I should reference the keys on the actual tables. I saw some examples for creating composite keys from an array which I did. The main questions are did I declare the composite keys correctly, am I creating the composite key reference from the array correctly, and how should I reference it all to append to the stringbuilder variable.
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And yes I kn ow it would be easier if I used Strongly Typed Dataset, but this is a clr sql stored procedure and have not found any examples on how to add a .XSD to a stored procedure. The add item option is not available, besides a bunch of typing
I had a post about how to disable monitors, but someone suggested just making it not possible to leave the primary screen. This was obviously a good suggestion, but im not sure how i would accomplish this.
I need to prevent the user from entering the ctrl, alt, delete, escape, and windows key. I also need to prevent the mouse from leaving the primary screen.
My program is a security login system. It requires a username and password to close, and i want to make sure that it cannot close unless the user supplies the correct username and password.
I'm using vb2005express for forms (front-end) and ms access database. I have a form with a master-detail setup. The problem I'm having is that when I set the primary key column to autonumber, I don't get the pk value generated in ms access database into my master datatable in forms when a new record is created. Then I tried setting the AutoIncreament to True in the pk column of the datatable in my dataset (forms). This generates a number in my pk column but its not the number generated in the database (since I think because the pk column is still set to AutoNumber). So I change the field property of my pk to Number in the access database and on my dataset (forms), i still have AutoIncrement to True.
This works okay since what it seems to be doing is getting the max value for the pk column when the datatable is filled upon form load. The problem now is that I normally don't do tableadapter.fill(datatable) at form load since I think there would be a performance issue if record counts around millions. What happens now is that when I create a new record, the pk generated is still 1 which will cause duplicate violation when saving to database. I'm not quite familiar with access features but in oracle, what I do is I create a sequence in database then I create a function that gets the next value of the sequence. Then at form load I set the datatable.column.default_value = get_sequence. How do I do this in ms access?
I am importing Tables from a Oracle DataBase, using a VB.NET dataAdapter. I use the "fill" comand to add the imported data to a DataSet. How is it possible to define a specific column of a DataTable as PrimaryKey, after the DataTable is already filled with data?
I have written a program which uses a SQL exception class and then use it show custom messages for the primary key violation. Also i want the primary key value that caused the violation. How can i get all the primary keys which generated the exception from the sqlexception object.[code]
Is it possible to have a Foreign Key as the Primary Key?
<Key()> Public Property AssignmentID() As Integer <ForeignKey("AssignmentID")> Public Overridable Property Assignment As Assignment Public Overridable Property User As User
For the code above I get an error:One or more validation errors were detected during model generation:System.Data.Edm.EdmAssociationEnd: : Multiplicity is not valid in Role 'AssignmentLocks_Assignment_Source' in relationship 'AssignmentLocks_Assignment'. Because the Dependent Role refers to the key properties, the upper bound of the multiplicity of the Dependent Role must be �1�.
I'm trying to create a table which has one (or none) record per assignment.
I have a database running on SQL server primary key is all set, my question is i dont want to allow duplicates in the primary key, i want everything to be uniqure. The database already has information in it, is there a away to set it so when i add a new row through the table adapter that it will recognise the last primary key value and increment it by +1?
I'm currently using this to get an object by it's primary key value.
I'm trying to find a way to create a similar method GetByIDs where I can pass an IEnumerable(of object) and do ids.contains(pk), but there's no Contains expression.
Public Function GetByID(Of T As Class)(ByVal pk As Object) As T Dim itemParam = Expression.Parameter(GetType(T), "item") Return GetTable(Of T).Single(
I' m trying to get the primary key which is "TestID" through the code below but I get an error "Range variable "testid" hides a variable in an enclosing block or a range variable previously defined in the query expression." What does this error mean ?
Dim oo As New DataClassesDataContext Dim o = (From k In oo.Tests Where k.Category.Equals(tempcategory) And k.Level.Equals("1")
i am trying to make a customer registration form. On the form i want to display the employee ID or Employee name who is servring or registring the customer. In short the employee who is logged in the system ,his Name or id should appear in the customer registration text box where the label says "served by"txtEmpName.Text
How do i reset a primary key to "0" at midnight For Every Day of the week. I would like To Start a fresh day @ "0" But keep The Information the I have. Previously Put in (it is For a booking program I am trying to create)
I m trying to make a simeple project in visual basic 2005 using visual studio 2005 sp1.
For isolating the problem i have just created project with a single form.
The form contains a masked text box (mask allows numeric(5 digits) int32 value )and a button named FIND.
Then i clicked on add a new data source wizard and added a data source (Microsoft.Jet.OLEDB.4.0 provider) and a microsoft access database (Library Management Project.mdb) . the database has a 5 digit primary key column named -BOOK_ID
i selected no when asked whether i want to add the local database to the output directory and modify connection.
then selected yes when asked whether i want to save the connection string.
then selected everythng when asked what database objects i want to add to dataset.
What i want the project to do when a person enters 5 digit integer value in masked text box and clicks the button FIND
a message should be displayed telling whether this value matches any of the primary key values.
so i wrote under the button click event
Dim DataRow As Library_Management_ProjectDataSet.BookDetailsRow
I just read that I cannot use a CommandBuilder for an Excel sheet as it has no primary key. (Wish I'd known that! I have to use Excel as the file is distributed elsewhere). I need to create commands manually. As a TEST sheet in Excel I have created 6 columns of data and loaded this data to a DataAdapter, then directly to a DataTable. A connection is made and the data is displayed in a DataGridView. I want to Update changes I typed manually in the DataGridView. The following code example I found manually builds an INSERT Command. But is the last part of the example code valid for UPDATE and DELETE? I'm trying to copy all changed data back to the Excel sheet.[code]...
Primary key must be unique....while inserting data into the database,i need to check whether the data already exist in the primary key column or not.......If not then only data will be inserted in the database else a msgbox will be displayed and data will not get inserted in the database....
I need to add data into a multi-column list, manually, in codes. I am using VB Express 2008. Could someone please hint me on how to do this with the following controls:
The ListBox or the ListView The Grid (I think it is the DataGridView)
Or anyother simple way of doing the stuff. All I want is simplicity.
in vb.net while entering a new entry i want to assign a record a unique id like in case of numeric i do this way
Dim ItemID As Integer KAYAReqConn.Open() SQLCmd = New SqlCommand("SELECT ISNULL(MAX(ItemID),0) AS ItemID from MstItem", ReqConn)
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in this case m using itemid as a unique id and the format is 1,2,3... and m finding out the max and assigning to a new record but how to assign if the previous id is of the a00001,a00002,a00003,a00004...so on. how i do i produce a unique id in this case
i am trying to write a code in which i need to perform a update but on primary keys how do i achieve it i have written the following code: kindly look at it let me know where m wrong
i am trying to write a code in which i need to perform a update but on primary keys how do i achieve iti have written the following code:
Protected Sub rgKMSLoc_UpdateCommand(ByVal source As Object, ByVal e As Telerik.Web.UI.GridCommandEventArgs) Handles rgKMSLoc.UpdateCommand Try KAYAReqConn.Open()
I would like to have some explaination about the characteristics of a primary key in the table of such database. This is for vb 2008 express edition,since im new to this language,if this is true, as far as i understand about the characteristic in setting the primary key on each field for true.My question is if you are doing an updates/edit records in your table using the DataContext,if you setup the primary key for true of one of your field in the table it would edit all records in one datarow but if you put the primary key for true in all fields except one of them,all the records in the data column of that field which primary key is false could be edited.Basically its impossible to edit all records in the datarow and all the records in the datacolumn of the table in such one event. Is there any further explaination about the characteristics of primary key in the table?