how to update dataset in rdlc parameters

SELECT department_name FROM departments WHERE department_id = 10 The following code shows a typical SELECT statement that does not use bind variables, with the value 10 specified in the WHERE clause of the statement. Using bind variables also improves query performance in the database, eliminates the need for special handling of literal quotation marks in the input, and protects against SQL injection attacks. Using bind variables makes the statement reusable with different input values. If the statement does exist in memory, Oracle Database can reuse it and skip the task of parsing and optimizing the statement. When a database receives a SQL statement, it determines if the statement has already been executed and stored in memory. Enter the login and data source.Īfter you connect, the departments list box shows Administration, the correct name for department number 10 in the HR schema, as requested by the SELECT statement.ĭescription of the illustration simple2.gifīind variables are placeholders inside a SQL statement. Zero-based ordinals passed to the accessors specify which column in the result set to return. NET data types and native Oracle data types.

Typed accessors, such as GetString, return native. In the Properties window, under Design, change the Name to departments.ĭescription of the illustration simple1.gifĪdd accessor type methods for retrieving data from the query result.ĭouble-click the connect button to edit the connect_click() method, and add the code indicated to the bottom of the try block.

In the Properties window, change the Text of the label to Department.įrom the Toolbox, under Window forms, select a ListBox and drag it onto Form1. From the View menu, select Designer.įrom the Toolbox, select a Label and drag it onto Form1.įrom the View menu, select Properties Window. OracleDataReader dr = cmd.ExecuteReader() ĭim dr As OracleDataReader = cmd.ExecuteReader() This enables you to read the result of the query. The application uses a ListBox to display the results.Ĭreate an OracleDataReader object, by adding the code indicated to the bottom of the Try block of the connect_Click() method. The ExecuteReader() method of an OracleCommand object returns an OracleDataReader object, which can be accessed to display the result on the form. This section demonstrates retrieving data from the database. OracleCommand cmd = new OracleCommand(sql, conn) cmd.CommandType = CommandType.Text ĭim sql As String = 'select department_name from departments' & _ĭim cmd As New OracleCommand(sql, conn) cmd.CommandType = CommandType.Text String sql = 'select department_name from departments' Use the new sql variable to create the OracleCommand object, and set the CommandType property to run a text command. SQL Statement string sql = 'select department_name from departments' + ' where department_id = 10' ĭim sql As String = 'select department_name from departments' & _ 'where department_id = 10' Note that the actual form in the designer still says Form1, as you renamed code files but not the actual form controls within the project.Ĭreate a string that represents the SQL query and add to the body of the try statement. The first copy is for the first part of the chapter, and the second copy for the second part of the chapter Name the copies Form2.cs or Form2.vb and Form3.cs or Form3.vb. To make copies, see the instructions in Appendix B, 'Copying a Form'. xx, from application HR_Connect_ xx in Chapter 3, 'Building a Simple. The OracleCommand object creates the request, sends it to the database, and returns the result. To view, edit, insert or delete data in a database, you must encapsulate a request in an OracleCommand object specifying a SQL command, stored procedure, or table name.

How to update dataset in rdlc parameters