--- /dev/null
+
+(in-package :cl-user)
+
+;; You must set these variables to appropriate values.
+(defvar *tutorial-database-type* nil
+ "Possible values are :postgresql,:postgresql-socket :mysql or :sqlite")
+(defvar *tutorial-database-name* ""
+ "The name of the database we will work in.")
+(defvar *tutorial-database-user* ""
+ "The name of the database user we will work as.")
+(defvar *tutorial-database-server* ""
+ "The name of the database server if required")
+(defvar *tutorial-database-password* ""
+ "The password if required")
+
+(sql:def-view-class employee ()
+ ((emplid
+ :db-kind :key
+ :db-constraints :not-null
+ :nulls-ok nil
+ :type integer
+ :initarg :emplid)
+ (first-name
+ :accessor first-name
+ :type (string 30)
+ :initarg :first-name)
+ (last-name
+ :accessor last-name
+ :type (string 30)
+ :initarg :last-name)
+ (email
+ :accessor employee-email
+ :type (string 100)
+ :nulls-ok t
+ :initarg :email)
+ (companyid
+ :type integer)
+ (company
+ :accessor employee-company
+ :db-kind :join
+ :db-info (:join-class company
+ :home-key companyid
+ :foreign-key companyid
+ :set nil))
+ (managerid
+ :type integer
+ :nulls-ok t)
+ (manager
+ :accessor employee-manager
+ :db-kind :join
+ :db-info (:join-class employee
+ :home-key managerid
+ :foreign-key emplid
+ :set nil)))
+ (:base-table employee))
+
+(sql:def-view-class company ()
+ ((companyid
+ :db-type :key
+ :db-constraints :not-null
+ :type integer
+ :initarg :companyid)
+ (name
+ :type (string 100)
+ :initarg :name)
+ (presidentid
+ :type integer)
+ (president
+ :reader president
+ :db-kind :join
+ :db-info (:join-class employee
+ :home-key presidentid
+ :foreign-key emplid
+ :set nil))
+ (employees
+ :reader company-employees
+ :db-kind :join
+ :db-info (:join-class employee
+ :home-key companyid
+ :foreign-key companyid
+ :set t)))
+ (:base-table company))
+
+;; Connect to the database (see the CLSQL documentation for vendor
+;; specific connection specs).
+(sql:connect `(,*tutorial-database-server*
+ ,*tutorial-database-name*
+ ,*tutorial-database-user*
+ ,*tutorial-database-password*)
+ :database-type *tutorial-database-type*)
+
+;; Record the sql going out, helps us learn what is going
+;; on behind the scenes
+(sql:start-sql-recording)
+
+;; Create the tables for our view classes
+;; First we drop them, ignoring any errors
+(ignore-errors
+ (sql:drop-view-from-class 'employee)
+ (sql:drop-view-from-class 'company))
+
+(sql:create-view-from-class 'employee)
+(sql:create-view-from-class 'company)
+
+
+;; Create some instances of our view classes
+(defvar employee1 (make-instance 'employee
+ :emplid 1
+ :first-name "Vladamir"
+ :last-name "Lenin"
+ :email "lenin@soviet.org"))
+
+(defvar company1 (make-instance 'company
+ :companyid 1
+ :name "Widgets Inc."))
+
+
+(defvar employee2 (make-instance 'employee
+ :emplid 2
+ :first-name "Josef"
+ :last-name "Stalin"
+ :email "stalin@soviet.org"))
+
+;; Lenin manages Stalin (for now)
+(sql:add-to-relation employee2 'manager employee1)
+
+;; Lenin and Stalin both work for Widgets Inc.
+(sql:add-to-relation company1 'employees employee1)
+(sql:add-to-relation company1 'employees employee2)
+
+;; Lenin is president of Widgets Inc.
+(sql:add-to-relation company1 'president employee1)
+
+(sql:update-records-from-instance employee1)
+(sql:update-records-from-instance employee2)
+(sql:update-records-from-instance company1)
+
+;; lets us use the functional
+;; sql interface
+(sql:locally-enable-sql-reader-syntax)
+
+
+(format t "The email address of ~A ~A is ~A"
+ (first-name employee1)
+ (last-name employee1)
+ (employee-email employee1))
+
+(setf (employee-email employee1) "lenin-nospam@soviets.org")
+
+;; Update the database
+(sql:update-records-from-instance employee1)
+
+(let ((new-lenin (car
+ (sql:select 'employee
+ :where [= [slot-value 'employee 'emplid] 1]))))
+ (format t "His new email is ~A"
+ (employee-email new-lenin)))
+
+
+;; Some queries
+
+;; all employees
+(sql:select 'employee)
+;; all companies
+(sql:select 'company)
+
+;; employees named Lenin
+(sql:select 'employee :where [= [slot-value 'employee 'last-name]
+ "Lenin"])
+
+(sql:select 'company :where [= [slot-value 'company 'name]
+ "Widgets Inc."])
+
+;; Employees of Widget's Inc.
+(sql:select 'employee
+ :where [and [= [slot-value 'employee 'companyid]
+ [slot-value 'company 'companyid]]
+ [= [slot-value 'company 'name]
+ "Widgets Inc."]])
+
+;; Same thing, except that we are using the employee
+;; relation in the company view class to do the join for us,
+;; saving us the work of writing out the SQL!
+(company-employees company1)
+
+;; President of Widgets Inc.
+(president company1)
+
+;; Manager of Josef Stalin
+(employee-manager employee2)