Example: IsNull (OraObject) Property

The following example shows the usage of IsNull property. Before running the sample code, make sure that you have the necessary datatypes and tables in the database. See Schema Description used in examples of OraObject/OraRef.

Dim OraSession as OraSession

Dim OraDatabase as OraDatabase

Dim OraDynaset as OraDynaset

Dim Address as OraObject

Dim AddressClone as OraObject

'Create the OraSession Object.

Set OraSession = CreateObject("OracleInProcServer.XOraSession")

'Create the OraDatabase Object by opening a connection to Oracle.

Set OraDatabase = OraSession.OpenDatabase("ExampleDb", "scott/tiger", 0&)

'create a dynaset object from person_tab

set OraDynaset = OraDatabase.CreateDynaset("select * from person_tab", 0&)

' insert a Null Address value instance in the table

OraDynaset.AddNew

OraDynaset.Fields("Name").value = "Eric"

OraDynaset.Fields("Addr").Value = Null

OraDynaset.update

'move to the newly added value instance

OraDynaset.MoveLast

'retrieve a address column from person_tab. This Address object points to Null value instance

set Address = OraDynaset.Fields("Addr").Value

'try to access attributes of Address .

' the following line will result an error

msgbox Address.Street '---------ERROR------------'

'use the IsNull property to check the nullstatus

If Address.IsNull = False Then

MsgBox Address!Street

End if