Populating a Data. Set from a Data. Adapter. The ADO. NETData. Set is a memory- resident representation of data that provides a consistent relational programming model independent of the data source. The Data. Set represents a complete set of data that includes tables, constraints, and relationships among the tables. Because the Data. Set is independent of the data source, a Data. Set can include data local to the application, and data from multiple data sources. How to fill multiple datatables in a dataset in a. your DataSet. Example: SqlDataAdapter da. what you need is Dataset - which can hold multiple tables and. · Here Mudassar Ahmed Khan has explained with an example, how to fill (populate) DataSet with records of multiple Tables in ASP.Net using C# and VB.Net. ![]() Interaction with existing data sources is controlled through the Data. Adapter. The Select. Command property of the Data. Adapter is a Command object that retrieves data from the data source. The Insert. Command, Update. Command, and Delete. Command properties of the Data. Can you have the InsertCommand property of a SqlDataAdapter set so that the Update() method is able to update a DataSet with multiple tables? Let's say that I want to. SqlDataAdapter Update Problem. Hi everybody, I'm using Mono 1.1.13. Adding multiple records to a tables i've got the following error. The thing i don't understand is. Interaction by using the DataSet and SqlDataAdapter. because the DataSet can hold multiple tables and this would. SqlDataAdapter’s Update method to. Adapter are Command objects that manage updates to the data in the data source according to modifications made to the data in the Data. Set. These properties are covered in more detail in Updating Data Sources with Data. Adapters. The Fill method of the Data. Adapter is used to populate a Data. Set with the results of the Select. ![]() Command of the Data. Adapter. Fill takes as its arguments a Data. Set to be populated, and a Data. · Visual C#.NET Client Application This section describes the steps to follow to reproduce the behavior and the steps to follow to resolve the behavior. · DataAdapter.Update .how to handle. Block you have the option to enroll a dataset update in a given. lost in how to handle inserts into multiple tables. Table object, or the name of the Data. Table to be filled with the rows returned from the Select. Command. Note Using the Data. Adapter to retrieve all of a table takes time, especially if there are many rows in the table. This is because accessing the database, locating and processing the data, and then transferring the data to the client is time- consuming. Pulling all of the table to the client also locks all of the rows on the server. To improve performance, you can use the WHERE clause to greatly reduce the number of rows returned to the client. You can also reduce the amount of data returned to the client by only explicitly listing required columns in the SELECT statement. Another good workaround is to retrieve the rows in batches (such as several hundred rows at a time) and only retrieve the next batch when the client is finished with the current batch. The Fill method uses the Data. Reader object implicitly to return the column names and types that are used to create the tables in the Data. Set, and the data to populate the rows of the tables in the Data. Set. Tables and columns are only created if they do not already exist; otherwise Fill uses the existing Data. Set schema. Column types are created as . NET Framework types according to the tables in Data Type Mappings in ADO. NET. Primary keys are not created unless they exist in the data source and Data. Adapter. Missing. Schema. Action is set to Missing. Schema. Action. Add. With. Key. If Fill finds that a primary key exists for a table, it will overwrite data in the Data. Set with data from the data source for rows where the primary key column values match those of the row returned from the data source. If no primary key is found, the data is appended to the tables in the Data. Set. Fill uses any mappings that may exist when you populate the Data. Set (see Data. Adapter Data. Table and Data. Column Mappings). Note If the Select. Command returns the results of an OUTER JOIN, the Data. Adapter does not set a Primary. Key value for the resulting Data. Table. You must define the Primary. Key yourself to make sure that duplicate rows are resolved correctly. For more information, see Defining Primary Keys. The following code example creates an instance of a Sql. Data. Adapter that uses a Sql. Connection to the Microsoft SQL Server Northwind database and populates a Data. Table in a Data. Set with the list of customers. The SQL statement and Sql. Connection arguments passed to the Sql. Data. Adapter constructor are used to create the Select. Command property of the Sql. Data. Adapter. Example' Assumes that connection is a valid Sql. Connection object. Dim query. String As String = _. SELECT Customer. ID, Company. Name FROM dbo. Customers". Dim adapter As Sql. Data. Adapter = New Sql. Data. Adapter( _. String, connection). Dim customers As Data. Set = New Data. Set. Fill(customers, "Customers"). Assumes that connection is a valid Sql. Connection object. String =. "SELECT Customer. ID, Company. Name FROM dbo. Customers". Sql. Data. Adapter adapter = new Sql. Data. Adapter(query. String, connection). Data. Set customers = new Data. Set(). adapter. Fill(customers, "Customers"). Note The code shown in this example does not explicitly open and close the Connection. The Fill method implicitly opens the Connection that the Data. Adapter is using if it finds that the connection is not already open. If Fill opened the connection, it also closes the connection when Fill is finished. This can simplify your code when you deal with a single operation such as a Fill or an Update. However, if you are performing multiple operations that require an open connection, you can improve the performance of your application by explicitly calling the Open method of the Connection, performing the operations against the data source, and then calling the Close method of the Connection. You should try to keep connections to the data source open as briefly as possible to free resources for use by other client applications. Multiple Result Sets If the Data. Adapter encounters multiple result sets, it creates multiple tables in the Data. Set. The tables are given an incremental default name of Table. N, starting with "Table" for Table. If a table name is passed as an argument to the Fill method, the tables are given an incremental default name of Table. Name. N, starting with "Table. Name" for Table. Name. Populating a Data. Set from Multiple Data. Adapters Any number of Data. Adapter objects can be used with a Data. Set. Each Data. Adapter can be used to fill one or more Data. Table objects and resolve updates back to the relevant data source. Data. Relation and Constraint objects can be added to the Data. Set locally, which enables you to relate data from dissimilar data sources. For example, a Data. Set can contain data from a Microsoft SQL Server database, an IBM DB2 database exposed through OLE DB, and a data source that streams XML. One or more Data. Adapter objects can handle communication to each data source. Example The following code example populates a list of customers from the Northwind database on Microsoft SQL Server, and a list of orders from the Northwind database stored in Microsoft Access 2. The filled tables are related with a Data. Relation, and the list of customers is then displayed with the orders for that customer. For more information about Data. Relation objects, see Adding Data. Relations and Navigating Data. Relations. ' Assumes that customer. Connection is a valid Sql. Connection object. Assumes that order. Connection is a valid Ole. Db. Connection object. Dim cust. Adapter As Sql. Data. Adapter = New Sql. Data. Adapter( _. SELECT * FROM dbo. Customers", customer. Connection). Dim ord. Adapter As Ole. Db. Data. Adapter = New Ole. Db. Data. Adapter( _. SELECT * FROM Orders", order. Connection). Dim customer. Orders As Data. Set = New Data. Set(). cust. Adapter. Fill(customer. Orders, "Customers"). Adapter. Fill(customer. Orders, "Orders"). Dim relation As Data. Relation = _. customer. Orders. Relations. Add("Cust. Orders", _. Orders. Tables("Customers"). Columns("Customer. ID"), _. customer. Orders. Tables("Orders"). Columns("Customer. ID")). Dim p. Row, c. Row As Data. Row. For Each p. Row In customer. Orders. Tables("Customers"). Rows. Console. Write. Line(p. Row("Customer. ID"). To. String()). For Each c. Row In p. Row. Get. Child. Rows(relation). Console. Write. Line(vb. Tab & c. Row("Order. ID"). To. String()). Assumes that customer. Connection is a valid Sql. Connection object. Assumes that order. Connection is a valid Ole. Db. Connection object. Sql. Data. Adapter cust. Adapter = new Sql. Data. Adapter(. "SELECT * FROM dbo. Customers", customer. Connection). Ole. Db. Data. Adapter ord. Adapter = new Ole. Db. Data. Adapter(. SELECT * FROM Orders", order. Connection). Data. Set customer. Orders = new Data. Set(). cust. Adapter. Fill(customer. Orders, "Customers").
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