Using retrieval arguments – PB Docs 2017

Defining retrieval arguments in the DataWindow
painter

You can select View>Column Specifications from the menu
bar. In the Column Specification view, a column of check boxes next
to the columns in the data source lets you identify the columns
users should be prompted for. This, like the Retrieval Arguments
prompt, calls the Retrieve method.

See Enhancing DataWindow
Objects.

• Retrieving the row in the Employee table for an employee ID
  entered into a text box. You must pass that information to the
  SELECT statement as an argument at runtime.

• Retrieving all rows from a table for a department selected
  from a drop-down list. The department is passed as an argument at
  runtime.

Using retrieval arguments at runtime

If a DataWindow object has retrieval arguments, call the
Retrieve method of the DataWindow control to retrieve data at
runtime and pass the arguments in the method.

To define retrieval arguments

1. In the SQL Select painter, select Design > Retrieval
   Arguments from the menu bar.

2. Enter a name and select a datatype for each argument.

   You can enter any valid SQL identifier for the argument
   name. The position number identifies the argument position in the
   Retrieve method you code in a script that retrieves to retrieve
   data into the DataWindow object.

3. Click Add to define additional arguments as needed and click
   OK when done.

   Specifying an array as a retrieval
   argument

   You can specify an array of values as your retrieval
   argument. Choose the type of array from the Type drop-down list in
   the Specify Retrieval Arguments dialog box. You specify an array
   if you want to use the IN operator in your WHERE clause to
   retrieve rows that match one of a set of values. For
   example:

   PowerBuilder

   SELECT * from employee WHERE dept_id IN (100, 200, 500)

   1	SELECT * from employee WHERE dept_id IN (100, 200, 500)

   retrieves all employees in department 100, 200, or 500. If
   you want your user to specify the list of departments to retrieve,
   you define the retrieval argument as a number array (such as 100,
   200, 500).

   In the code that does the retrieval, you declare an array
   and reference it in the Retrieve method., as in:

   PowerBuilder

   int x[3] // Now populate the array with values // such as x[1] = sle_dept.Text, and so on, // then retrieve the data, as follows. dw_1.Retrieve(x) Integer x[]= new Integer[3]; x[0]=new Integer(100); x[1]=new Integer(200); x[2]=new Integer(500); dw1.retrieve(x);

   1 2 3 4 5 6 7 8 9 10

   int x[3] // Now populate the array with values // such as x[1] = sle_dept.Text, and so on, // then retrieve the data, as follows. dw_1.Retrieve(x) Integer x[]= new Integer[3]; x[0]=new Integer(100); x[1]=new Integer(200); x[2]=new Integer(500); dw1.retrieve(x);

   PowerBuilder passes the appropriate comma-delimited list to
   the method (such as 100, 200, 500 if x[1] = 100, x[2] = 200, and
   x[3] = 500 if x[0] = 100, x[1] = 200, and x[2] = 500).

   When building the SELECT statement, you reference the
   retrieval arguments in the WHERE or HAVING clause, as described in
   the next section.