If I would connect to database I would run a query like this: "Select distinct Column1, column2 from tablename where somefield=somevalue order by column2". How can I run this query to a datatable? I know .select but that's not enough like dataset.datatable("name").select(filter,short). Still need distinct.
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I am trying to distinct on multiple columns and get datarows from datatable. but getting error.
Dim query As IEnumerable(Of DataRow) =
(From row As DataRow In SourceTable.AsEnumerable() _
Select row.Field(Of String)("ColumnName1"),
[Code]....
I want another datatable with distinct row based on given columns from SourceTable.
I am using strongly typed dataset and have many tables in that. The problem is now I want to filter data from
GetData()
function which has a query like
select * from table_name
How can I filter a particular table and distinct values from it. Also if I try to filter it return all column but rest have null values except the one I asked, so I cannot assign it as a datasource to a datagrid or combobox. How can I do this..
I have a "result" which is DataTable and I like to get the x distinct values(City) and convert it back to DataTable how do I do this the code below gives me an error
Dim query = (From x In results.AsEnumerable()
Select (x.Field(Of String)("City"))).Distinct().CopyToDataTable()
so what I want is records of distinct cities I can get that but the problem I am having is converting it back to Datable.
Edited:I am using "where" in this statement and it does convert to Table(works fine) but not on "select"
Dim results = (From myRow In ds.Tables(1).AsEnumerable()
Where (myRow.Field(Of String)("xxxx") = xxxx)
Select myRow).Distinct().CopyToDataTable()
I have a DataTable that has several hundred rows.I want to get a row count of distinct values in a particular column.For example, I have a DataTable of Product Orders, but I want to get the number of unique Customers.
I was using this code, but I can't rely on it because my binding source is filtered from time to time.If my binding source has filtered out all rows datatable.DefaultView returns 0 rows.
I have a datatable which has been dynamically generated from FoxPro tables using a UNION Select statement. e.g.SELECT * FROM x UNION SELECT * FROM y UNION SELECT * FROM Z ORDER By v_alue1This produces a datatable with about 100 rows, each containing many fields, one of which is c_olor. From this datatable, I would like to select the distinct colors and then output in a dropdown.I have a public class Color which just has one property which I can then use as the DataTextField and DataValueField for the dropdownlist
Public Class Color
Private _c_olor As String
Public Property c_olor() As String
[code].....
I am trying to get distinct rows based on multiple columns (attribute1_name, attribute2_name) and get datarows from datatable using Linq-to-Dataset.[code]How to do thin Linq-to-dataset?
View 3 RepliesIs it possible to select distinct values from a DataTable?
View 5 Repliesi fill a datatable in a typed dataset.. it has cities and states but I want to pull just distinct states and bind it to a control etc.. there is the filter, but i havent found a way to do distinct or group by. got to be a way without adding more datatables and filling them with data thats already there right?
View 1 RepliesI've a collection with the data like this.[code]...
how can select the distinct data using linq?
I am building a custom search control in VB.NET and came across a problem getting distinct records into my datagridview. I want to bring exact matches back first so I run 2 of the same query on the same table with a slight difference:
select ... like "code%"
select ... like "%code%"
I have a datatable that I need to get distinct records from; I am append records from a sql query to the end of the datatable so I cannot use a union in sql to return the dataset (I want to preserve the order which the rows are added) I have been using this which is working fine for 2 fields:
dt2 = dt.DefaultView.ToTable(True, "Code", "Name")
But when I have 3 (or more) fields I get duplicates ONLY for the row I am querying:
dt2 = dt.DefaultView.ToTable(True, "Code", "Name", "Initial")
select ... like "initial%"
select ... like "%intial%"
I am clearing the datagridview.source before rebuilding this. Is there a way to get the distinct rows this way or should I just build something myself to remove the duplicates from the second datatable before appending them to the new table?
The following data is created by joining two sql tables together:I would like to group together distinct rows of DateStamp/UserName/ StudentName/ InstructorName/TableName/PrimaryKey (I'll call this 'group records') and then group under these ColumnName/PreviousValue/NewValue (I'll call this 'subgroup records')The end result would be that I could iterate through the 'group records' - there would be 5. In each 'group record', I could then iterate through the 'subgroup records'. The 5 groups would contain 3, 2, 5, 2 and 1 subgroup records respectively.What would be the syntax to create a query to do this? Ideally this would be in a vb.net linq syntax.
View 1 RepliesI have a datatable as shown in the figure. Let me explain my required based on this image. I have 7 rows of data. The rows 1 and 2 contains columns till UnitSqcNo same. I want only row 3 among the two. In general I want select all the rows with distinct model, unittype, unit and rest with greater CompId. ie the table should look like
View 1 Repliesload the contents of a query from a dataTable Adapter into a datatable?
View 2 RepliesI created a RDCL in the designer. I would like the User to Determine what is shown in the Report. How can I change the query at runtime? (ex. changing the customer Name)
This is the query that I have in the properties:
SELECT [Date], Address, Customer, Orders
FROM Report_qry
WHERE (Customer= 'JohnDoe')
I have a DataTable "dt1" that has thousands of rows.
Columns are:
- Type_And_Model
- Val_1
- Val_2
- Val_3
- Val_4
There are only about 30 different "Type_And_Model"-types.How can I insert into a new DataTable (dt2) only distinct "Type_And_ Model" types with the sum of their specific values and total appearance number?
dt1 - DataTable with thousands of rows
Type1 2 2 5 5
Type1 4 2 7 5
Type2 2 2 5 8
Type1 2 2 9 5
Type3 3 2 5 5
Type1 6 2 5 7
Type3 2 7 5 9
Type1 8 2 9 5
.....
INTO =>
dt2 -DataTable with disinct types and their sum values + appearance numbers.
Type1 22 10 35 27 5
Type2 2 2 5 8 1
Type3 5 9 10 14 2
I have an untyped dataset which is populated at runtime. I need to look for a Datarow in the datatable containing a specific value in one of its column ("ID") and when found should set the other column value ("Value") on the same Datarow. How to do it?I tried the following to get the DataRow:
Dim foundrow As DataRow = dt.Rows.Find(ID)where dt is my Datatable and ID is a String variable which is to be found.I always get Nothing as return. I checked the datatable just before executing that line: it has over 100 rows and the the ID to be found is there. I stil get Nothing as return.
[Code]...
How do I query a DataTable where a value has an apostrophe in it? For example, my datatable has a lastname column and I want to search for the name "O'Bryan", how would I do it? With an SQL query I would just use a parameter & it would take care of the apostrophe automatically. Is there a way to use parameters with a DataTable?
View 5 RepliesI'm using VB.Net to create a windows form application. One form has a DataGridView that displays data from a SQLServer table via a TableAdapter and BindingSource whose filter is set as I need it. Elsewhere on the same form I would like to show totals for four columns of the same table, but from a totally different set of rows. All I've been able to figure out is to create another TableAdapter - but this seems foolish since the SQL table data has already been brought into my application by the first TableAdapter.Is there a way to run a query on the DataTable that was filled by the first TableAdapter, and how do I get the query results?
View 8 RepliesI do have a datatable filled from a flatfile (say .txt). After the datatable is populated, I manipulate the data. After datamanipulation I want to do some analysis of the content of the datatable. For this analysis, I need to aggregate the data.
To keep it simple, let's say I have single orders of customers in the datatable and now I want to get the total order amount for each customer (SQL: SELECT Customer, Count(Ordervalue) FROM Ordertable GROUP BY Customer).
I have pulled information from a database into a datatable (dtCustomerInfo) then I expanded on the columns by processing the data and I can display this in a datagridview without any problem. However, the data is in detail and I want to ultimately summarize by customer name.The code below has a commented sql statement that is the statement I ultimately want but it is not working. However, the idea is that I want to Select from one datatable into another but run aggregate sum on several columns so that I will get one record per customer showing totals for each column.So I broke it down to just pull all data possible into the second table.[code]I do know the grouping in the current select * statement does nothing but my issue is more that the columns do not show up.
View 3 RepliesI have a function (GetData) that parses a SQL string, makes a connection to a SQL Server and dumps the result to a DataTable. It works perfectly on a series of SQL calls I have. I have new query I have added and now the function balks at the adapter.Fill(table) call. I do not understand why the call fails. The SQL portion works fine when run directly against the SQL database (Management Studio). I am thinking the fuctions not capable of dealing with the subquery somehow, just not sure why.
Bindingsource4.DataSource = GetData("SELECT QTY,ITEM_NUMBER,DESCRIPTION,(Select STATUS_TEXT From ITEM_STATUS_LIST Where STATUS_VALUE = Line_Items.Status) FROM(LINE_ITEMS) JOIN PURCHASE_ORDERS ON
[Code]....
How can i write this query with LINQ to a FoxPro database?SELECT count(*) FROM Table group by item1I wrote it as below, but it doesn't work
Dim Query
Dim dt As New DataTable
Dim da = New Odbc.OdbcDataAdapter("SELECT * FROM table1",connection)
[code].....
I do have the following problem extracting records from a datatable, based on date.
I am using Datatable.compute to sum the relevant rows, at least I'm trying to!
CrTot is a variable of type double
BankTrans is a datatable
dteRecDte is a datetimepicker component
CrTot = BankTrans.Compute("sum(bank_amount)",
"bank_amount > 0 And date_bank_reconciled <="
& dteRecDte.Value.Date)
doing the sum calculation on it's own works properly. I now need to check that the date of the "date_bank_reconciled" field is less than or equal to the value of the date entered in the datetimepicker "dteRecDte.Value.Date", so that only rows with a date either less than or the same as that in the datetimepciker are returned.
I have an SQL table(for example, it have 1 column "kod" with 3 rows:1,2,3 ). To operate it, I used class LINQ to SQL and I create tmp dataset with one table, with one column "col" with values - 2,3,4. To operate with this tmp table i use IEnumerable(T).I want to find only new values in tmp table and write its in SQL table. To find this values, i want to use LINQ query. Queris to each table are worked well. But query for 2 tables don't work.
Imports System.Linq
Imports System.Data.Linq
Public Class Form1
[code]....
How do I perform an sql query onto a DataTable not a Database table?
View 1 RepliesI wrote a procedure that builds a DataTable in memory using data stored on our DB2 database. The function builds a Multi-Level Bill of Materials (BoM), meaning that the data cannot simply be queried. The function works great and returns a nicely arranged DataTable object. However, I then need to query the in-memory DataTable against other tables on our server. What would be the best way to approach this problem? Should I make a DataTableAdapter for the Server tables and then build a DataView? I don't have too much experience yet with Data objects. (By the way, I looked into LINQ to DB2 and even installed IBM's addin's, but our server doesn't seem to support it at this time.)
View 6 Repliesi need to query the datatable & set the outcome as datagridview controls datasource
vb.net
Private Sub Txt_Search_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Txt_Search.TextChanged
'routine objective:- Filter datatable & set the datagridview datasource
[code]....
I'm trying to query a DataTable to get a collection of rows but I'm finding that my search string has to be the exact length of the columns width. So, for example this won't work:
Dim rows As DataRow() = (From r In myTable.AsEnumerable() Where r.Field(Of String)("fname") = "Bob").ToArray()
...but this will:
Dim rows As DataRow() = (From r In myTable.AsEnumerable() Where r.Field(Of String)("fname") = "Bob ").ToArray()
The search term ("Bob") has to be padded with spaces to make it equal in length to the column width (10 characters). Is this how it's supposed to work or am I doing something wrong?Also, how can I do a LIKE search? So for example, I want to search for all names that start with "Bo" or whatever. ie. "Bo*".
I have a string like "Hello'World" and a Data Table with some records in it. One of those records is "Hello'World".he problem is, when I do a .Select in the Data Table, it only tries to search for the "Hello" part and throws an error on "World" because it interprets the ' (single. cuote) like the closing cuote on sql.DataTable.select("text = 'Hello'World'")I have gone through msdn doc, and it says I can escape some characters with [] brackets or f.slashes , but I just can't figure out: .select("text = 'Hello[']world'")
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