examples/clsql-tutorial.lisp

   1 (asdf:operate 'asdf:load-op 'clsql)
   2
   3 (in-package #:clsql-user)
   4
   5 ;; You must set these variables to appropriate values.
   6 (defvar *tutorial-database-type* nil
   7   "Possible values are :postgresql :postgresql-socket, :mysql,
   8 :oracle, :odbc, :aodbc or :sqlite")
   9 (defvar *tutorial-database-name* "clsqltut"
  10   "The name of the database we will work in.")
  11 (defvar *tutorial-database-user* ""
  12   "The name of the database user we will work as.")
  13 (defvar *tutorial-database-server* ""
  14   "The name of the database server if required")
  15 (defvar *tutorial-database-password* ""
  16   "The password if required")
  17
  18 (clsql:def-view-class employee ()
  19   ((emplid
  20     :db-kind :key
  21     :db-constraints :not-null
  22     :type integer
  23     :initarg :emplid)
  24    (first-name
  25     :accessor first-name
  26     :type (string 30)
  27     :initarg :first-name)
  28    (last-name
  29     :accessor last-name
  30     :type (string 30)
  31     :initarg :last-name)
  32    (email
  33     :accessor employee-email
  34     :type (string 100)
  35     :initarg :email)
  36    (companyid
  37     :type integer
  38     :initarg :companyid)
  39    (company
  40     :accessor employee-company
  41     :db-kind :join
  42     :db-info (:join-class company
  43                           :home-key companyid
  44                           :foreign-key companyid
  45                           :set nil))
  46    (managerid
  47     :type integer
  48     :initarg :managerid)
  49    (manager
  50     :accessor employee-manager
  51     :db-kind :join
  52     :db-info (:join-class employee
  53                           :home-key managerid
  54                           :foreign-key emplid
  55                           :set nil)))
  56   (:base-table employee))
  57
  58 (clsql:def-view-class company ()
  59   ((companyid
  60     :db-kind :key
  61     :db-constraints :not-null
  62     :type integer
  63     :initarg :companyid)
  64    (name
  65     :type (string 100)
  66     :initarg :name)
  67    (presidentid
  68     :type integer
  69     :initarg :presidentid)
  70    (president
  71     :reader president
  72     :db-kind :join
  73     :db-info (:join-class employee
  74                           :home-key presidentid
  75                           :foreign-key emplid
  76                           :set nil))
  77    (employees
  78     :reader company-employees
  79     :db-kind :join
  80     :db-info (:join-class employee
  81                           :home-key companyid
  82                           :foreign-key companyid
  83                           :set t)))
  84   (:base-table company))
  85
  86 ;; Connect to the database (see the CLSQL documentation for vendor
  87 ;; specific connection specs).
  88 (case *tutorial-database-type*
  89   ((:mysql :postgresql :postgresql-socket)
  90    (clsql:connect `(,*tutorial-database-server*
  91                     ,*tutorial-database-name*
  92                     ,*tutorial-database-user*
  93                     ,*tutorial-database-password*)
  94                   :database-type *tutorial-database-type*))
  95   ((:odbc :aodbc :oracle)
  96    (clsql:connect `(,*tutorial-database-name*
  97                     ,*tutorial-database-user*
  98                     ,*tutorial-database-password*)
  99                   :database-type *tutorial-database-type*))
 100   (:sqlite
 101    (clsql:connect `(,*tutorial-database-name*)
 102                   :database-type *tutorial-database-type*)))
 103
 104 ;; Record the sql going out, helps us learn what is going
 105 ;; on behind the scenes
 106 (clsql:start-sql-recording)
 107
 108 ;; Create the tables for our view classes
 109 ;; First we drop them, ignoring any errors
 110 (ignore-errors
 111  (clsql:drop-view-from-class 'employee)
 112  (clsql:drop-view-from-class 'company))
 113
 114 (clsql:create-view-from-class 'employee)
 115 (clsql:create-view-from-class 'company)
 116
 117
 118 ;; Create some instances of our view classes
 119 (defvar company1 (make-instance 'company
 120                               :companyid 1
 121                               :name "Widgets Inc."
 122                               ;; Lenin is president of Widgets Inc.
 123                               :presidentid 1))
 124
 125 (defvar employee1 (make-instance 'employee
 126                                :emplid 1
 127                                :first-name "Vladamir"
 128                                :last-name "Lenin"
 129                                :email "lenin@soviet.org"
 130                                :companyid 1))
 131
 132 (defvar employee2 (make-instance 'employee
 133                                :emplid 2
 134                                :first-name "Josef"
 135                                :last-name "Stalin"
 136                                :email "stalin@soviet.org"
 137                                :companyid 1
 138                                ;; Lenin manages Stalin (for now)
 139                                :managerid 1))
 140
 141 (clsql:update-records-from-instance employee1)
 142 (clsql:update-records-from-instance employee2)
 143 (clsql:update-records-from-instance company1)
 144
 145 ;; lets use the functional sql interface
 146 (clsql:locally-enable-sql-reader-syntax)
 147
 148 (format t "The email address of ~A ~A is ~A"
 149         (first-name employee1)
 150         (last-name employee1)
 151         (employee-email employee1))
 152
 153 (setf (employee-email employee1) "lenin-nospam@soviets.org")
 154
 155 ;; Update the database
 156 (clsql:update-records-from-instance employee1)
 157
 158 (let ((new-lenin (car
 159                   (clsql:select 'employee
 160                               :where [= [slot-value 'employee 'emplid] 1]
 161                               :flatp t))))
 162   (format t "His new email is ~A"
 163           (employee-email new-lenin)))
 164
 165
 166 ;; Some queries
 167
 168 ;; all employees
 169 (clsql:select 'employee)
 170 ;; all companies
 171 (clsql:select 'company)
 172
 173 ;; employees named Lenin
 174 (clsql:select 'employee :where [= [slot-value 'employee 'last-name]
 175                                 "Lenin"])
 176
 177 (clsql:select 'company :where [= [slot-value 'company 'name]
 178                                "Widgets Inc."])
 179
 180 ;; Employees of Widget's Inc.
 181 (clsql:select 'employee
 182             :where [and [= [slot-value 'employee 'companyid]
 183                            [slot-value 'company 'companyid]]
 184                         [= [slot-value 'company 'name]
 185                            "Widgets Inc."]])
 186
 187 ;; Same thing, except that we are using the employee
 188 ;; relation in the company view class to do the join for us,
 189 ;; saving us the work of writing out the SQL!
 190 (company-employees company1)
 191
 192 ;; President of Widgets Inc.
 193 (president company1)
 194
 195 ;; Manager of Josef Stalin
 196 (employee-manager employee2)