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?
View 2 RepliesOn 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]
View 1 RepliesI came across a problem with using a BindingSource as my DataGridViews.DataSource. Whenever I applied a filter to a column in the BindingSource and the user makes changes that don't match the column filter the DataGridViewRows would automatically disappear. A similar thing would happen when applying a Sort to a column. If the user made any changes the DridGirdViewRows would automatically sort causing rows to be moved around. This was not ideal for my application and there isn't anyway to stop this from happening with the BindingSource.
To correct this issue I have to use subsets of data. I use a DataView to apply the filter and sort to the main DataTable, which creates the subset DataTable.The problem is when I use the DataView.ToTable method I loose the Primary Key and RowError information. So I have to reapply this information everytime the user filters or sorts the DataGridView.Is there a better way to get a subset DataTable?[code]...
I'm trying to query a datatable to establish the primary key [identity column], by querying each columns autoincrement property. However its always false (for the column which is the Idenity/PK).
Querying the tables primary key collection reveals that the datatable doesn't think it has a PK.;
Dim dc As DataColumn() = dt.PrimaryKey
Debug.WriteLine(dc.Count) 'Result is 0
[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.
I have imported a single table of a database into a dataset. I would like to find a row containing a specific value and then update some of the data in several columns of that row. When I use the code below, I get this message:"System.Data.MissingPrimaryKeyException: Table doesn't have a primary key."
The first block of code is where I setup my connection and paramters. The updateDB sub is where I want to perform the update. The database was setup in SQL Server. If I have a primary key specified for the database in SQL Server, shouldn't it carry through with the data adapter fill?
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I am new to ADO.Net and I mistakenly using the dataset as how we use recordsets in ADO., I know that it is possible to create a Datatable which will only reside in the memory and hold data. What I need to create is like this.
1. Create Datatable.
2. Fill it with sample data at least 3 lines.
3. Transfer the data from datatable to database (access,sqlsrvr etc).
I am new at asp.net, so I would be glad, if anybody could help me in this case... I scanned already the internet for answers, unfortunately with no success..I have a grid view, and this is loaded by a sql data table, this table has 2 keys (RezeptNr and Zutatnr). When I wanna update a row in the data grid, the RowUpdating event fires, so I need to read the Basket Session, what has the complete object stored. I put this in a DataTable (dt1), so far so good..The problem is line: Dim dr As System.Data.DataRow = dt1.Rows.Find(id) Here the compiler alerts, that I have two keys, and he cannot select the data sentence with the find method. I tried it with datatable.select command, that works, but then I have the data sentence in an array, but I need to update the data row of the data table.
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I have a datatable which has 5 column. It is possible to copy only its 2 column in and save it into new datatable.I used this code but it copies all the 5 column
Code:
Dim qry As DataTable = (From obj In temptable Where obj.Item("Column1") = 0 _
Select obj).CopyToDataTable
i used this one but it is not supported
Code:
Dim qry As DataTable = (From obj In temptable Where obj.Item("Column1") = 0 _
Select obj.item("Column1"), obj.item("Column2")).CopyToDataTable
Ok so this is going to take some explaining. The process I am trying to do is grab data from a table function in SQL and then fill a dataset with the returned values. I then have to run this query twice more to query an alternative number table. Then add to the same table as the previous queries.This needs to be as fast as possible, so I am currently using an adapter.fill to populate the datasets and then a dataset.merge to put them all into one table.
The problem is the query can return duplicates which waste time and space, because of this I made column 3(part_ID) the primary key to stop duplicates.When this is run with the .merge it quits at the first instance of a duplication and doesn't continue with the population.
[Code]...
What is the easiest way to automatically fill a datetime column in an SQL data table with the date the row was created? Using SQL Server 2005 if that matters.
EDIT: I've tried using GETDATE() for default and that works for an INSERT Query but not when the TableAdapter adds the row.
How to apply primary key on sno column in the following dataset. [code]
View 1 RepliesI'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?
How to apply primary key on sno column in the following dataset
dim sql = "select * from employees"
Dim da As new SqlClient.SqlDataAdapter (sql,con)
'ds.Clear()
[Code]......
How i can import row from TABLE1 to TABLE2 without primary keyfield or adding correct value to primary key
i tried with two different codes, but result is same, it says: "In the column "Key"a constraint on the uniqueness.[code]...
I have a data table, i want to add a new column on that table, the data in that new column will depend in the data from another column. Now i can think of two ways to accomplish this, first is loop through the whole table and do the statements to get my new columns appropriate data. the second approach would be to give the new column an expression, then convert the table to xml (to remove the expression) then convert the xml string back to datatable.
Now, is there any other way around this? what could be the most optimized way in solving this task?
After Filling a DataTable in GridView's DataSource . A column with check box Type appears but it created as read only column and I can't enable it or make it editable... even i tried .readonly = false and still can't be edited
View 1 RepliesI have a string say, str = "system.Int16" I want to add a column in DataTable say, dt = new DataTable()I want DataType for that column as per 'str', i.e. System.Int16 Then How to? dt.Columns.Add("MyColumn", ...)
View 2 RepliesCan't add a new column for DataTable
View 2 RepliesI have a dataset with just 1 datatable and 1 row but with 2 columns.I want to get the value of the 1st column.How can I get it in vb.net
View 3 Repliesi have a Datatable having following result from database
ID Name Class FeeName Amount
9 gumman hgjgh 6Th Fine 0
9 gumman hgjgh 6Th Tution Fee 3000
9 gumman hgjgh 6Th Lebority Fee 500
10 AAdil Hussain 5Th Fine 0
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I have a sql stored procedure that returns a certain group of columns in my datatable. How can I move (let's say) the column in the first position, to the last position before I export the datatable to excel ?
Dim myConn As New SqlConnection(strConnection)
Dim myCmd As New SqlCommand(strSQL, myConn)
Dim dt As DataTable = New DataTable()
Dim da As SqlDataAdapter = New SqlDataAdapter(strSQL, myConn)
[code]....
I have a csv file that comes in I put it into a dataset and do a little manuipulation of the appearance of how the data is presented and then I put it back out into a different csv file that our 3rd party application will except. I was importing it into SQL Server and then doing a select statement to grab the data back out in the format I required. However I'd really like to eliminate the need for the SQL Server use.
So my question is how do I add in the 1st column of a CSV file the column name "KC" with a value of "1" there will only be 1 rows worth of data, mind you it's 55 columns long but there is nothing I can do about that, it's the way it has to be.So do I do this in the DataTable or when I create the CSV file? And how do I do this?
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Is it possible to have a button column in a data table like there is in DataGridView?
View 2 RepliesI need to limit the amount of columns being returned from a datatable from 14 to 5 or 6. Date, Hour and 3 to 4 decimal columns. Is it possible to do something like a SQL 'Like' to specify which columns I want?
View 8 RepliesSo i create a datatable from a table i can't directly view(i.e. using sql server management). I want to find the column names that are in the datatable, what would be the correct way do this?
View 3 RepliesHow to insert a column in datatable at Perticular index in vb 2003.
View 4 RepliesI need to Quarry from Data Table Like
select Name, Address from myDataTable where name = 'x'
and
select distinct(name) from myDataTable
What's wrong with my LINQ query ?
Dim s = (From rowItem In i.AsEnumerable() _
Select rowItem("COUNTER")).Sum()
I'm trying to Sum all the value in column 'Counter' in my Datatable. 'Overload resolution failed because no accessible 'SUM' accepts this number of arguments.
My problem is that i want to use the Compute method for a datatable.[code]The name of the column of that i want to sumarize is 2012, but it seems that the compute method doesn't recognize it as a column and throw this exception Syntax error in aggregate argument: Expecting a single column with a qualifier 'Child'.It is not possible to me to change the name of the column, what can i do in this case to sumarize the datatable and save it in a variable
View 4 Replies