FAQ'S ON DATA SET

How do I update tables in the dataset?

Updating a table in ADO.Net is very interesting and easy. You need to follow these steps to update, insert and delete records:

1 • The Data Adapter class (SqlDataAdapter) has properties for each of the insert, update and delete commands. First of all we need to prepare the command (SqlCommand) and add it to the data adapter object. The commands are simple SQL commands with parameters. You may use the Visual Studio .Net designer to easily create these commands.

2 • Secondly we need to add parameters to these commands. The parameters are simply the names of the data table fields involved in the particular command. Visual Studio .Net also build it for you in its Data Adapter configuration wizard.

3 • The two steps described above are done only once in the application. For each insert, update and delete; we insert, update and delete the corresponding data row (DataRow) of the data table (DataTable) object.

4 • After any update we call the Update() method of the data adapter class by supplying to it, the dataset and table name as parameters. This updates our local dataset.

5 • Finally we call the AcceptChanges() method of the dataset object to store the changes in the dataset to the physical database.

How do I use a CommandBuilder object to prepare the update commands in my dataset?

Each data provider has a command builder object that prepares the update, insert and delete commands for you. You can use these (SqlCommandBuilder, OracleCommandBuilder, OleDbCommandBuilder, OdbcCommandBuilder) objects to generate commands automatically using the Select command you specified when defining the data adapter.

What are the general steps for updating the records in dataset?

1• The Data Adapter class (SqlDataAdapter) has properties for each of the insert, update and delete commands. First of all we need to prepare the command (SqlCommand) and add it to the data adapter object.

2• Secondly we need to add parameters to these commands.

3• The two steps described above are done only once in the application. For each insert, update and delete; we insert, update and delete the corresponding data row (DataRow) of the data table (DataTable) object.

4• After any update we call the Update() method of the data adapter class by supplying to it, the dataset and table name as parameters. This updates our local dataset.

5• Finally we call the AcceptChanges() method of the dataset object to store the changes in the dataset to the physical database.

How do I update the dataset with the updates in records?

You can update the dataset by calling the Update() method of the data adapter.

C# Version

DataTable dt = ds.Tables["Article"];
dt.Rows[2]["lines"] = 600;

da.Update(ds, "Article");


VB.Net Version


Dim dt = ds.Tables("Article")
dt.Rows(2)("lines") = 700

da.Update(ds, "Article")


Here ‘da’ and ‘ds’ are the references of the DataAdapter and DataSet objects respectively.

How do I update the physical database with the changes in the dataset?

You can update the physical database by calling the AcceptChanges() method of the data set.

C# Version

DataTable dt = ds.Tables["Article"];
dt.Rows[2]["lines"] = 600;

da.Update(ds, "Article");
ds.AcceptChanges();

VB.Net Version

Dim dt = ds.Tables("Article")
dt.Rows(2)("lines") = 700

da.Update(ds, "Article")
ds.AcceptChanges()
Here ‘da’ and ‘ds’ are the references of the DataAdapter and DataSet objects respectively.

How do I update a record in the table using ADO.Net dataset?

Once you have the UpdateCommand prepared in the data adapter, you can update individual records simply by updating the field values in the data table’s rows. The above code demonstrate how we can update the ‘lines’ field of the third record of the table ‘Article’ .

C# Version

DataTable dt = ds.Tables["Article"];
dt.Rows[2]["lines"] = 600;

da.Update(ds, "Article");
ds.AcceptChanges();

VB.Net Version

Dim dt = ds.Tables("Article")
dt.Rows(2)("lines") = 700

da.Update(ds, "Article")
ds.AcceptChanges()

How do I insert a record in the table using ADO.Net dataset?

To insert a record in the data table, you create an object of the DataRow using the DataTable object. Then you set the appropriate field values and finally add it to the DataTable’s Rows collection.

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