When creating the recordset in dreamwever using the Advanced view, to use a session variable, you need to create a variable in the recordset.
Create the SQL as:
WHERE table1.field1 LIKE '%exampleText1%' AND table2.fieldB LIKE '%paramSession%'
The click the plus button in the variable section:
Name: paramSession
Type: Integer
Defualt Value: -1
Run Time Value: $_SESSION['exampleTextB']
This will cause "paramSession" in the SQL Above to be replaced with the value stored in the session variable if it is set or -1 if it is not.