anchor.diff:  ;; Some queries
   
   ;; all employees
  -(sql:select 'employee)
  +(clsql:select 'employee)
   ;; all companies
  -(sql:select 'company)
  +(clsql:select 'company)
   
   ;; employees named Lenin
  -(sql:select 'employee :where [= [slot-value 'employee 'last-name]
  +(clsql:select 'employee :where [= [slot-value 'employee 'last-name]
   				"Lenin"])
   
  -(sql:select 'company :where [= [slot-value 'company 'name]
  +(clsql:select 'company :where [= [slot-value 'company 'name]
   			       "Widgets Inc."])
   
   ;; Employees of Widget's Inc.
  -(sql:select 'employee
  +(clsql:select 'employee
   	    :where [and [= [slot-value 'employee 'companyid]
   			   [slot-value 'company 'companyid]]
   			[= [slot-value 'company 'name]
  
positive.code: (defvar *tutorial-database-password* "" 
    "The password if required")
  
  (sql:def-view-class employee ()
    ((emplid
      :db-kind :key
      :db-constraints :not-null
  
negative.code: (asdf:operate 'asdf:load-op 'clsql)
  
  (in-package #:clsql-user)
  
  ;; You must set these variables to appropriate values. 
  (defvar *tutorial-database-type* nil 
  