How do I perform a join between two DataTables in a Dataset?
I created a DataRelation between two tables….then what?
I'm looking at one explanation on how to do it (http://www.emmet-gray.com/Articles/DataTableJoins.htm) which involves copying rows from tables to a result table?
Is there a better way to do this?
...
I can't find the answer to this anywhere, and before I start pawing through generated code with Reflector I thought it'd be worth asking:
Suppose I have the following LINQ query run against DataTables in a DataSet:
var list =
from pr in parentTable.AsEnumerable()
join cr in childTable.AsEnumerable() on cr.Field<int>("ParentID") ...
I want to show a master / detail relationship using two datagridviews and DataRelation in C#.
The relation between the master and the detail table is an ID from type string (and there is no chance to change the ID to type integer).
It seems like the DataGridView is not able to update the detail view when changing the row in the master ...
Hello,
I want to show a master / detail relationship using two datagridviews and DataRelation in C#.
The relation between the master and the detail table is an ID from type string (and there is no chance to change the ID to type integer).
It seems like the DataGridView is not able to update the detail view when changing the row in the...
Hi,
i have the following piece of VB.NET code:
Dim conn As New MySql.Data.MySqlClient.MySqlConnection(ConnectionString)
conn.Open()
Dim sql = "SELECT * FROM users"
Dim com = New MySql.Data.MySqlClient.MySqlCommand(sql, conn)
Dim ds As New DataSet("dsUsers")
Dim da As New MySql.Data.MySqlClient.MySqlDataAdapte...
Say I have a DataGridView (named dataGridView) that is displaying a Strongly Typed DataTable (named ChildDataTable).
dataGridView has a DataGridViewCheckBoxColumn (named parentIDColumn) that is bound to a Field Property ParentID on each ChildDataRow in ChildDataTable.
ParentID is a foreign key that relates ChildDataTable to another Dat...
Guys,
I have a winforms application with two DataGridViews displaying a master-detail relationship from my Person and Address tables. Person table has a PersonID field that is auto-incrementing primary key. Address has a PersonID field that is the FK.
I fill my DataTables with DataAdapter and set Person.PersonID column's AutoIncrement...
I am running into a problem when setting the UpdateBatchSize property to a number > 1 on my data adapter. I only get an error when I have a very specific type of DataRelationship on the table. Consider:
Table JobProductColorSize
Columns:
Id : long //is a primary key
ParentAssemblyId : long?
Therefore I have a DataRelation created ...
A C# program I am working on will need to export data to one or more tables of data. Some columns of these tables will be related to one another, such that the ID column of of one table may be reference by the cell of another table. This seems like the common case for setting up a DataRelation. But I'm trying to understand how these rela...
Hello Im using C# 3.5 and I try to solve the "more than one entity situation" using a single query for each one and then joined them with DataRelation, so after I realized that I've tryed to show data on this way :
DataColumn parentColumn = dataSet.Tables["Suppliers"].Columns["SupplierID"];
DataColumn childColumn = dataSet.Tables["Prod...
Hi,
How do I get all rows from ITEM table, which are children of a parent ITEM table row, where relationship is stored separately? How can I do a join to do this? "get all rows from ITEM table, which are children of this specific ITEM table row, all child items from this parent item, where relationship is stored in separate RELATIONSH...
C# (.NET 3.5)
I have an SQLite database with two tables - employees (the first column being id INTEGER PRIMARY KEY), and holidays (id INTEGER - meaning the ID of the employee; start DATE, end DATE - self-explanatory).
My form contains textboxes, checkboxes etc. to represent the employee details - but say I'd also like a list box, listi...
My LINQ query is not producing the expected output below. Basically, it's the sum of table3.cost corresponding to table2.code and table2.class categorized by table1.alias and ordered by table1.priority. I added two DataRelation's to the DataSet:
ds.Relations.Add("Table1Table2", ds.Tables[1].Columns("ID"), ds.Tables[2].Columns("ParentI...
Hello,
I have a complex problem, could you please help me.
The problem:
I have a form with a TabControl. There are two TabPages in the first is a dataGridView and in the second are multiple comboboxes.
DataGridView is filled with data from Table1, on the other tab the first combobox datasource is set to TableCB1, the second combo...
Hi,
I have two unrelated tables in SQL Server. I want to form a relationship with them via C# so the database diagram in SQL Server has the relationship line etc (the code may have flaws apart from the lack of using statements etc, other than that let me know).
I have this code so far:
SqlConnection con = new SqlConnection("Data So...
i have a situation like this:
TOWN_PLAN_UNIT table:
ID NAME
123 Block123
456 Block345
BUILDING_TOWN_PLAN_UNIT table:
UNIT_ID BUILDING_ID
123 999
123 908
456 333
456 999
BUILDING
ID NAME
999 Building999
I want to gather all data of block456 to a tree and I use DataRelations:
TOWN_PLAN_UNIT.ID -> BUILDING_TOWN_PLAN_U...
How would I model a relationship between multiple entities where one entity could be part of two separate, unrelated, hierarchies and each entity could be related to 1 or more other entities in a non-hierarchical fashion? I would like to do this in only 2 or 3 tables in the database.
I currently have it modeled into two tables:
Entit...