r9804: * doc/ref-ooddl.xml: minor changes to syntax and examples entries
[clsql.git] / doc / ref-ooddl.xml
index 568cb1af80d0eb0c0bcf9cf1431e19b735cc5586..5c51f4b5f35ff3f3c636cea7c2e8e37485a047e8 100644 (file)
@@ -8,10 +8,28 @@
 <!-- Object Oriented Data Definition Language --> 
 <reference id="ref-ooddl"> 
   <title>Object Oriented Data Definition Language (OODDL)</title> 
-    <partintro>
+  <partintro>
     <para>
-      <!-- introduction --> 
+      The Object Oriented Data Definition Language (OODDL) provides
+      access to relational SQL tables using Common Lisp Object System
+      (CLOS) objects.  SQL tables are mapped to CLOS objects with the
+      SQL columns being mapped to slots of the CLOS object.
     </para>
+    <para> 
+      The mapping between SQL tables and CLOS objects is defined with
+      the macro <link
+      linkend="def-view-class"><function>def-view-class</function></link>. SQL
+      tables are created with <link
+      linkend="create-view-from-class"><function>create-view-from-class</function></link>
+      and SQL tables can be deleted with <link
+      linkend="drop-view-from-class"><function>drop-view-from-class</function></link>.
+    </para>
+    <note>
+      <para>The above functions refer to the Lisp
+      <emphasis>view</emphasis> of the SQL table. This Lisp view
+      should not be confused with SQL <function>VIEW</function>
+      statement.</para>
+    </note>
   </partintro>
 
   <refentry id="standard-db-object">
     <refsect1>
       <title>Class Precedence List</title>
       <para>
-        <simplelist type="inline">
-          <member><type>standard-db-object</type></member>
-          <member><type>standard-object</type></member>
-          <member><type>t</type></member>
-        </simplelist>
+       <simplelist type="inline">
+         <member><type>standard-db-object</type></member>
+         <member><type>standard-object</type></member>
+         <member><type>t</type></member>
+       </simplelist>
       </para>
     </refsect1>
     <refsect1>
       of all &clsql; View Classes.</para>
     </refsect1>
     <refsect1>
-      <title class="contenttitle">Class details</title>
+      <title>Class details</title>
       <programlisting>(defclass STANDARD-DB-OBJECT ()(...))</programlisting>
     </refsect1>
     <refsect1>
-      <title class="contenttitle">Slots</title>
+      <title>Slots</title>
       <para>
-        <simplelist> 
-          <property>slot VIEW-DATABASE is of type T</property>
-        </simplelist> 
+       <simplelist> 
+         <member>slot VIEW-DATABASE is of type (OR NULL DATABASE)
+         which stores the associated database for the
+         instance.</member>
+       </simplelist> 
       </para>
     </refsect1>
   </refentry>
 
-  <refentry id="default-varchar-length">
+  <refentry id="default-string-length">
     <refnamediv>
-      <refname>*DEFAULT-VARCHAR-LENGTH*</refname>
-      <refpurpose><!-- purpose --></refpurpose>
+      <refname>*DEFAULT-STRING-LENGTH*</refname>
+      <refpurpose>Default length of SQL strings.</refpurpose>
       <refclass>Variable</refclass>
     </refnamediv>
     <refsect1>
       <title>Value Type</title>
       <para>
-        <!-- value type --> 
+       Fixnum
       </para> 
     </refsect1>
     <refsect1>
       <title>Initial Value</title>
-      <para><symbol>nil</symbol></para>
+      <para><parameter>255</parameter></para>
     </refsect1>
     <refsect1>
-      <title>Description</title>
-      <!-- description --> 
+      <title>Description</title> 
+      <para>
+       If a slot of a class defined by
+       <function>def-view-class</function> is of the type
+       <parameter>string</parameter> or
+       <parameter>varchar</parameter> and does not have a length
+       specified, then the value of this variable is used as SQL
+       length.
+      </para>
     </refsect1>
     <refsect1>
       <title>Examples</title>
       <screen>
-        <!-- examples --> 
+(let ((*default-string-length* 80))
+  (def-view-class s80 ()
+    ((a :type string)
+     (b :type (string 80))
+     (c :type varchar))))
+=> #&lt;Standard-Db-Class S80 {480A431D}>
+
+(create-view-from-class 's80)   
+=> 
+(table-exists-p [s80]) 
+=> T
       </screen>
+      <para>
+       The above code causes a SQL table to be created with the SQL command
+      </para>
+      <screen>CREATE TABLE (A VARCHAR(80), B CHAR(80), C VARCHAR(80))</screen>
     </refsect1>
     <refsect1>
       <title>Affected By</title>
-      <para>None.</para>
+      <para>
+        Some SQL backends do not support
+        <parameter>varchar</parameter> lengths greater than 255.
+      </para>
     </refsect1>
     <refsect1>
       <title>See Also</title>
     </refsect1>
     <refsect1>
       <title>Notes</title>
-      <para>None.</para>
+      <para>This is a CLSQL extension to the CommonSQL API.</para>
     </refsect1>
   </refentry>
 
   <refentry id="create-view-from-class">
     <refnamediv>
       <refname>CREATE-VIEW-FROM-CLASS</refname>
-      <refpurpose><!-- purpose --></refpurpose>
+      <refpurpose>Create a SQL table from a <glossterm linkend="gloss-view-class">View Class</glossterm>.</refpurpose>
       <refclass>Function</refclass>
     </refnamediv>
     <refsect1>
       <title>Syntax</title>
       <synopsis>
-      <function> (CREATE-VIEW-FROM-CLASS VIEW-CLASS-NAME &amp;KEY (DATABASE *DEFAULT-DATABASE*)) [function]</function> => <returnvalue><!-- result --></returnvalue></synopsis>
+      <function>create-view-from-class</function> <replaceable>view-class-name</replaceable> &amp;key <replaceable>database</replaceable> <replaceable>transactions</replaceable> => <returnvalue><!-- no values --></returnvalue></synopsis>
     </refsect1>
     <refsect1>
       <title>Arguments and Values</title>
       <variablelist>
-        <!-- arguments and values --> 
+       <varlistentry>
+         <term><parameter>view-class-name</parameter></term>
+         <listitem>
+           <para>
+             The name of a <glossterm linkend="gloss-view-class">View
+             Class</glossterm> that has been defined with <link
+             linkend="def-view-class"><function>def-view-class</function></link>.
+           </para>
+         </listitem>
+       </varlistentry>
+       <varlistentry>
+         <term><parameter>database</parameter></term>
+         <listitem>
+           <para>
+             The <glossterm
+             linkend="gloss-database-object">database</glossterm> in
+             which to create the SQL table. This will default to the
+             value of <symbol>*default-database*</symbol>.
+           </para>
+         </listitem>
+       </varlistentry>
+       <varlistentry>
+         <term><parameter>transactions</parameter></term>
+         <listitem>
+           <para>
+             When &nil; specifies that a table type which does not
+             support transactions should be used.
+           </para>
+         </listitem>
+       </varlistentry>
       </variablelist>
     </refsect1>
     <refsect1>
       <title>Description</title>
-      <para>Creates a table as defined by the View Class
-      VIEW-CLASS-NAME in DATABASE which defaults to
-      *DEFAULT-DATABASE*.
+      <para>
+       Creates a table as defined by the <glossterm
+       linkend="gloss-view-class">View Class</glossterm>
+       <parameter>view-class-name</parameter> in
+       <parameter>database</parameter>.
       </para>
     </refsect1>
     <refsect1>
       <title>Examples</title>
       <screen>
-        <!-- examples -->
+(def-view-class foo () ((a :type (string 80))))
+=> #&lt;Standard-Db-Class FOO {4807F7CD}>
+(create-view-from-class 'foo)
+=> 
+(list-tables)
+=> ("FOO")
       </screen>
     </refsect1>
     <refsect1>
       <title>Side Effects</title>
       <para>
-        <!-- side effects --> 
+       Causes a table to be created in the SQL database.
       </para>
     </refsect1>
     <refsect1>
       <title>Affected by</title>
       <para>
-        <simplelist>
-          <!-- affected by --> 
-        </simplelist>
+       Most SQL database systems will signal an error if a table
+       creation is attempted when a table with the same name already
+       exists. The SQL user, as specified in the database connection,
+       must have sufficient permission for table creation.
       </para>
     </refsect1>
     <refsect1>
       <title>Exceptional Situations</title>
       <para>
-        <!-- execeptional situations -->
+       A condition will be signaled if the table can not be created
+       in the SQL database.
       </para>
     </refsect1>
     <refsect1>
       <title>See Also</title>
       <para>
-        <simplelist>
-          <!-- see also --> 
-        </simplelist>
+       <simplelist>
+         <member><link linkend="def-view-class"><function>def-view-class</function></link></member>
+         <member><link linkend="drop-view-from-class"><function>drop-view-from-class</function></link></member>
+       </simplelist>
       </para>
     </refsect1>
     <refsect1>
       <title>Notes</title>
       <para>
-        <!-- notes --> 
+       Currently, only &mysql; supports transactionless
+       tables. &clsql; provides the ability to create such tables for
+       applications which would benefit from faster table access and
+       do not require transaction support.
+      </para>
+      <para>
+       The case of the table name is determined by the type of the
+       database. &mysql;, for example, creates databases in upper-case
+       while &postgresql; uses lowercase.
       </para>
     </refsect1>
   </refentry>
   <refentry id="def-view-class">
     <refnamediv>
       <refname>DEF-VIEW-CLASS</refname>
-      <refpurpose><!-- purpose --></refpurpose>
-      <refclass>Function</refclass>
+      <refpurpose>Defines CLOS classes with mapping to SQL database.</refpurpose>
+      <refclass>Macro</refclass>
     </refnamediv>
     <refsect1>
       <title>Syntax</title>
       <synopsis>
-      <function> (DEF-VIEW-CLASS CLASS SUPERS SLOTS &amp;REST CL-OPTIONS) [macro]</function> => <returnvalue><!-- result --></returnvalue></synopsis>
+      <function>def-view-class</function> <replaceable>name</replaceable> <replaceable>superclasses</replaceable> <replaceable>slots</replaceable> &amp;rest <replaceable>class-options</replaceable> => <returnvalue>class</returnvalue></synopsis>
     </refsect1>
     <refsect1>
       <title>Arguments and Values</title>
       <variablelist>
-        <!-- arguments and values --> 
+       <varlistentry>
+         <term><parameter>name</parameter></term>
+         <listitem>
+           <para>
+             The class name.
+           </para>
+         </listitem>
+       </varlistentry>
+       <varlistentry>
+         <term><parameter>superclasses</parameter></term>
+         <listitem>
+           <para>
+             The superclasses for the defined class.
+           </para>
+         </listitem>
+       </varlistentry>
+       <varlistentry>
+         <term><parameter>slots</parameter></term>
+         <listitem>
+           <para>
+             The class slot definitions.
+           </para>
+         </listitem>
+       </varlistentry>
+       <varlistentry>
+         <term><parameter>class options</parameter></term>
+         <listitem>
+           <para>
+             The class options.
+           </para>
+         </listitem>
+       </varlistentry>
+       <varlistentry>
+         <term><parameter>class</parameter></term>
+         <listitem>
+           <para>
+             The defined class.
+           </para>
+         </listitem>
+       </varlistentry>
       </variablelist>
     </refsect1>
+    <refsect1>
+      <title>Slot Options</title>
+      <itemizedlist>
+       <listitem>
+         <para>
+           <parameter>:db-kind</parameter> - specifies the kind of
+           database mapping which is performed for this slot and
+           defaults to <parameter>:base</parameter> which indicates
+           that the slot maps to an ordinary column of the database
+           table. A <parameter>:db-kind</parameter> value of
+           <parameter>:key</parameter> indicates that this slot is a
+           special kind of <parameter>:base</parameter> slot which
+           maps onto a column which is one of the unique keys for the
+           database table, the value <parameter>:join</parameter>
+           indicates this slot represents a join onto another
+           <glossterm linkend="gloss-view-class">View Class</glossterm>
+           which contains View Class objects, and the value
+           <parameter>:virtual</parameter> indicates a standard CLOS
+           slot which does not map onto columns of the database
+           table.
+         </para>
+       </listitem>
+       <listitem>
+         <para>
+           <parameter>:db-info</parameter> - if a slot is specified
+           with <parameter>:db-kind</parameter>
+           <parameter>:join</parameter>, the slot option
+           <parameter>:db-info</parameter> contains a property list
+           which specifies the nature of the join. The valid members
+           of the list are:
+         </para>
+         <itemizedlist>
+           <listitem>
+             <para>
+               <parameter>:join-class</parameter>
+               <emphasis>class-name</emphasis> - the name of the
+               class to join on.
+             </para>
+           </listitem>
+           <listitem>
+             <para>
+               <parameter>:home-key</parameter>
+               <emphasis>slot-name</emphasis> - the name of the slot
+               of this class for joining
+             </para>
+           </listitem>
+           <listitem>
+             <para>
+               <parameter>:foreign-key</parameter>
+               <emphasis>slot-name</emphasis> - the name of the slot
+               of the <parameter>:join-class</parameter> for joining
+             </para>
+           </listitem>
+           <listitem>
+             <para>
+               <parameter>:target-slot</parameter>
+               <emphasis>target-slot</emphasis> - this is an optional
+               parameter. If specified, then the join slot of the
+               defining class will contain instances of this target
+               slot rather than of the join class. This can be useful
+               when the <parameter>:join-class</parameter> is an
+               intermediate class in a
+               <emphasis>many-to-many</emphasis> relationship and the
+               application is actually interested in the
+               <parameter>:target-slot</parameter>.
+             </para>
+           </listitem>
+           <listitem>
+             <para>
+               <parameter>:retrieval</parameter>
+               <emphasis>time</emphasis> - The default value is
+               <parameter>:deferred</parameter>, which defers filling
+               this slot until the value is accessed. The other valid
+               value is <parameter>:immediate</parameter> which
+               performs the SQL query when the instance of the class
+               is created. In this case, the
+               <parameter>:set</parameter> is automatically set to
+               &nil;
+             </para>
+           </listitem>
+           <listitem>
+             <para>
+               <parameter>:set</parameter> <emphasis>set</emphasis> -
+               This controls what is stored in the join slot.  The
+               default value is &t;. When <emphasis>set</emphasis> is
+               &t; and <emphasis>target-slot</emphasis> is undefined,
+               the join slot will contain a list of instances of the
+               join class. Whereas, if
+               <emphasis>target-slot</emphasis> is defined, then the
+               join slot will contain a list of pairs of
+               <emphasis>(target-value join-instance)</emphasis>.
+               When <emphasis>set</emphasis> is &nil;, the join slot
+               will contain a single instances.
+             </para>
+           </listitem>
+         </itemizedlist>
+       </listitem>
+       <listitem>
+         <para>
+           <parameter>:type</parameter> - for slots of
+           <parameter>:db-kind</parameter> <parameter>:base</parameter> or
+           <parameter>:key</parameter>, the <parameter>:type</parameter> slot
+           option has a special interpretation such that Lisp
+           types, such as string, integer and float are
+           automatically converted into appropriate SQL types for
+           the column onto which the slot maps. This behaviour may
+           be overridden using the <parameter>:db-type</parameter> slot
+           option. The valid values are:
+           <simplelist>
+             <member>
+               <parameter>string</parameter> - a variable length
+               character field up to <link
+               linkend="default-string-length">*default-string-length*</link>
+               characters.
+             </member>
+             <member>
+               <parameter>(string n)</parameter> - a fixed length
+               character field <parameter>n</parameter> characters
+               long.
+             </member>
+             <member>
+               <parameter>varchar</parameter> - a variable length
+               character field up to <link
+               linkend="default-string-length">*default-string-length*</link>
+               characters.
+             </member>
+             <member>
+               <parameter>(varchar n)</parameter> - a variable length
+               character field up to <parameter>n</parameter>
+               characters in length.
+             </member>
+             <member>
+               <parameter>char</parameter> - a single character field
+             </member>
+             <member><parameter>integer</parameter> - signed integer
+             at least 32-bits wide</member>
+             <member><parameter>(integer n)</parameter></member>
+             <member><parameter>float</parameter></member>
+             <member><parameter>(float n)</parameter></member>
+             <member><parameter>long-float</parameter></member>
+             <member><parameter>number</parameter></member>
+             <member><parameter>(number n)</parameter></member>
+             <member><parameter>(number n p)</parameter></member>
+             <member>
+               <parameter>tinyint</parameter> - An integer column 8-bits
+               wide. [not supported by all database backends]
+             </member>
+             <member>
+               <parameter>smallint</parameter> - An integer column 16-bits
+               wide. [not supported by all database backends]
+             </member>
+             <member>
+               <parameter>bigint</parameter> - An integer column 
+               64-bits wide. [not supported by all database backends]
+             </member>
+             <member>
+               <parameter>universal-time</parameter> - an integer
+               field sufficiently wide to store a
+               universal-time. On most databases, a slot of this
+               type assigned a SQL type of
+               <parameter>BIGINT</parameter>
+             </member>
+             <member>
+               <parameter>wall-time</parameter> - a slot which stores
+               a date and time in a SQL timestamp column. &clsql;
+               provides a number of time manipulation functions to
+               support objects of type <type>wall-time</type>.
+             </member>
+             <member>
+               <parameter>duration</parameter> - stores a
+               <type>duration</type> structure.  &clsql; provides
+               routines for <type>wall-time</type> and
+               <type>duration</type> processing.
+             </member>
+             <member><parameter>boolean</parameter> - stores a &t; or
+             &nil; value.</member>
+             <member>
+               <parameter>generalized-boolean</parameter> - similar
+               to a <parameter>boolean</parameter> in that either a
+               &t; or &nil; value is stored in the SQL
+               database. However, any Lisp object can be stored in
+               the Lisp object. A Lisp value of &nil; is stored as
+               <constant>FALSE</constant> in the database, any
+               other Lisp value is stored as
+               <constant>TRUE</constant>.
+             </member>
+             <member>
+               <parameter>keyword</parameter> - stores a keyword
+             </member> 
+             <member><parameter>symbol</parameter> - stores a symbol</member>
+             <member>
+               <parameter>list</parameter> - stores a list by writing
+               it to a string. The items in the list must be able to
+               be readable written.
+             </member>
+             <member><parameter>vector</parameter> - stores a vector
+             similarly to <parameter>list</parameter></member>
+             <member><parameter>array</parameter> - stores a array
+             similarly to <parameter>list</parameter></member>
+           </simplelist>
+         </para>
+         
+       </listitem>
+       <listitem>
+         <para>
+           <parameter>:column</parameter> - specifies the name of
+           the SQL column which the slot maps onto, if
+           <parameter>:db-kind</parameter> is not
+           <parameter>:virtual</parameter>, and defaults to the
+           slot name. If the slot name is used for the SQL column
+           name, any hypens in the slot name are converted
+           to underscore characters.
+         </para>
+       </listitem>
+       <listitem>
+         <para>
+           <parameter>:void-value</parameter> - specifies the value
+           to store in the Lisp instance if the SQL value is NULL and
+           defaults to NIL.
+         </para>
+       </listitem>
+       <listitem>
+         <para>
+           <parameter>:db-constraints</parameter> - is a keyword
+           symbol representing an SQL column constraint expression or
+           a list of such symbols. The following column constraints
+           are supported: <symbol>:not-null</symbol>,
+           <symbol>:primary-key</symbol>, <symbol>:unique</symbol>,
+           <symbol>:unsigned</symbol> (&mysql; specific),
+           <symbol>:zerofill</symbol> (&mysql; specific) and
+           <symbol>:auto-increment</symbol> (&mysql; specific).
+         </para>
+       </listitem>
+       <listitem>
+         <para>
+           <parameter>:db-type</parameter> - a string to specify the SQL
+           column type. If specified, this string overrides the SQL
+           column type as computed from the <parameter>:type</parameter>
+           slot value.
+         </para>
+       </listitem>
+      </itemizedlist>
+    </refsect1>
+    <refsect1>
+      <title>Class Options</title>
+      <para>
+       <itemizedlist>
+         <listitem>
+           <para>
+             <parameter>:base-table</parameter> - specifies the name
+             of the SQL database table. The default value is the
+             class name. Like slot names, hypens in the class name
+             are converted to underscore characters.
+           </para>
+         </listitem>
+       </itemizedlist>
+      </para>
+    </refsect1>
     <refsect1>
       <title>Description</title>
-      <para>Creates a View Class called CLASS whose slots SLOTS can
-      map onto the attributes of a table in a database. If SUPERS is
-      nil then the superclass of CLASS will be STANDARD-DB-OBJECT,
-      otherwise SUPERS is a list of superclasses for CLASS which
-      must include STANDARD-DB-OBJECT or a descendent of this
-      class. The syntax of DEFCLASS is extended through the addition
-      of a class option :base-table which defines the database table
-      onto which the View Class maps and which defaults to
-      CLASS. The DEFCLASS syntax is also extended through additional
-      slot options. The :db-kind slot option specifies the kind of
-      DB mapping which is performed for this slot and defaults to
-      :base which indicates that the slot maps to an ordinary column
-      of the database table. A :db-kind value of :key indicates that
-      this slot is a special kind of :base slot which maps onto a
-      column which is one of the unique keys for the database table,
-      the value :join indicates this slot represents a join onto
-      another View Class which contains View Class objects, and the
-      value :virtual indicates a standard CLOS slot which does not
-      map onto columns of the database table. If a slot is specified
-      with :db-kind :join, the slot option :db-info contains a list
-      which specifies the nature of the join. For slots of :db-kind
-      :base or :key, the :type slot option has a special
-      interpretation such that Lisp types, such as string, integer
-      and float are automatically converted into appropriate SQL
-      types for the column onto which the slot maps. This behaviour
-      may be over-ridden using the :db-type slot option which is a
-      string specifying the vendor-specific database type for this
-      slot's column definition in the database. The :column slot
-      option specifies the name of the SQL column which the slot
-      maps onto, if :db-kind is not :virtual, and defaults to the
-      slot name. The :void-value slot option specifies the value to
-      store if the SQL value is NULL and defaults to NIL. The
-      :db-constraints slot option is a string representing an SQL
-      table constraint expression or a list of such strings.
+      <para>
+       Creates a <glossterm linkend="gloss-view-class">View
+       Class</glossterm> called <parameter>name</parameter> whose
+       slots <parameter>slots</parameter> can map onto the attributes
+       of a table in a database. If
+       <parameter>superclasses</parameter> is &nil; then the
+       superclass of <parameter>class</parameter> will be
+       <parameter>standard-db-object</parameter>, otherwise
+       <parameter>superclasses</parameter> is a list of superclasses
+       for <parameter>class</parameter> which must include
+       <parameter>standard-db-object</parameter> or a descendent of
+       this class.
       </para>
+
     </refsect1>
     <refsect1>
       <title>Examples</title>
+      <para>
+       The following examples are from the &clsql; test suite.
+      </para>
       <screen>
-        <!-- examples -->
+(def-view-class person (thing)
+  ((height :db-kind :base :accessor height :type float
+           :initarg :height)
+   (married :db-kind :base :accessor married :type boolean
+            :initarg :married)
+   (birthday :type clsql:wall-time :initarg :birthday)
+   (bd-utime :type clsql:universal-time :initarg :bd-utime)
+   (hobby :db-kind :virtual :initarg :hobby :initform nil)))
+  
+(def-view-class employee (person)
+  ((emplid
+    :db-kind :key
+    :db-constraints :not-null
+    :type integer
+    :initarg :emplid)
+   (groupid
+    :db-kind :key
+    :db-constraints :not-null
+    :type integer
+    :initarg :groupid)
+   (first-name
+    :accessor first-name
+    :type (varchar 30)
+    :initarg :first-name)
+   (last-name
+    :accessor last-name
+    :type (varchar 30)
+    :initarg :last-name)
+   (email
+    :accessor employee-email
+    :type (varchar 100)
+    :initarg :email)
+   (ecompanyid
+    :type integer
+    :initarg :companyid)
+   (company
+    :accessor employee-company
+    :db-kind :join
+    :db-info (:join-class company
+                         :home-key ecompanyid
+                         :foreign-key companyid
+                         :set nil))
+   (managerid
+    :type integer
+    :initarg :managerid)
+   (manager
+    :accessor employee-manager
+    :db-kind :join
+    :db-info (:join-class employee
+                         :home-key managerid
+                         :foreign-key emplid
+                         :set nil))
+   (addresses
+    :accessor employee-addresses
+    :db-kind :join
+    :db-info (:join-class employee-address
+                         :home-key emplid
+                         :foreign-key aemplid
+                         :target-slot address
+                         :set t)))
+  (:base-table employee))
+
+(def-view-class company ()
+  ((companyid
+    :db-kind :key
+    :db-constraints :not-null
+    :type integer
+    :initarg :companyid)
+   (groupid
+    :db-kind :key
+    :db-constraints :not-null
+    :type integer
+    :initarg :groupid)
+   (name
+    :type (varchar 100)
+    :initarg :name)
+   (presidentid
+    :type integer
+    :initarg :presidentid)
+   (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 groupid)
+                         :foreign-key (ecompanyid groupid)
+                         :set t))))
+
+(def-view-class address ()
+  ((addressid
+    :db-kind :key
+    :db-constraints :not-null
+    :type integer
+    :initarg :addressid)
+   (street-number
+    :type integer
+    :initarg :street-number)
+   (street-name
+    :type (varchar 30)
+    :void-value ""
+    :initarg :street-name)
+   (city
+    :column "city_field"
+    :void-value "no city"
+    :type (varchar 30)
+    :initarg :city)
+   (postal-code
+    :column zip
+    :type integer
+    :void-value 0
+    :initarg :postal-code))
+  (:base-table addr))
+
+;; many employees can reside at many addressess
+(def-view-class employee-address ()
+  ((aemplid :type integer :initarg :emplid)
+   (aaddressid :type integer :initarg :addressid)
+   (verified :type boolean :initarg :verified)
+   (address :db-kind :join
+           :db-info (:join-class address
+                                 :home-key aaddressid
+                                 :foreign-key addressid
+                                 :retrieval :immediate)))
+  (:base-table "ea_join"))
+
+(def-view-class deferred-employee-address ()
+  ((aemplid :type integer :initarg :emplid)
+   (aaddressid :type integer :initarg :addressid)
+   (verified :type boolean :initarg :verified)
+   (address :db-kind :join
+           :db-info (:join-class address
+                                 :home-key aaddressid
+                                 :foreign-key addressid
+                                 :retrieval :deferred
+                                 :set nil)))
+  (:base-table "ea_join"))
       </screen>
     </refsect1>
     <refsect1>
       <title>Side Effects</title>
-      <para>
-        <!-- side effects --> 
-      </para>
+      <para>Creates a new CLOS class.</para>
     </refsect1>
     <refsect1>
       <title>Affected by</title>
       <para>
-        <simplelist>
-          <!-- affected by --> 
-        </simplelist>
+       Nothing.
       </para>
     </refsect1>
     <refsect1>
       <title>Exceptional Situations</title>
       <para>
-        <!-- execeptional situations -->
+       None.
       </para>
     </refsect1>
     <refsect1>
       <title>See Also</title>
       <para>
-        <simplelist>
-          <!-- see also --> 
-        </simplelist>
+       <simplelist>
+         <member><link linkend="create-view-from-class"><function>create-view-from-class</function></link></member>
+         <member><link linkend="standard-db-object"><parameter>standard-db-object</parameter></link></member>
+         <member><link linkend="drop-view-from-class"><function>drop-view-from-class</function></link></member>
+       </simplelist>
       </para>
     </refsect1>
     <refsect1>
       <title>Notes</title>
       <para>
-        <!-- notes --> 
+       The actual SQL type for a column depends up the database type
+       in which the SQL table is stored. As an example, the view
+       class type <parameter>(varchar 100)</parameter> specifies a
+       SQL column type <parameter>VARCHAR(100)</parameter> in &mysql;
+       and a column type <parameter>VARCHAR2(100)</parameter> in
+       &oracle;
+      </para>
+      <para>
+       The actual lisp type for a slot may be different than the
+       value specified by the <parameter>:type</parameter> attribute.
+       For example, a slot declared with "<parameter>:type (string
+       30)</parameter>" actually sets the slots Lisp type as
+       <parameter>(or null string)</parameter>. This is to allow a
+       &nil; value or a string shorter than 30 characters to be
+       stored in the slot.
       </para>
     </refsect1>
   </refentry>
   <refentry id="drop-view-from-class">
     <refnamediv>
       <refname>DROP-VIEW-FROM-CLASS</refname>
-      <refpurpose><!-- purpose --></refpurpose>
+      <refpurpose>Delete table from SQL database.</refpurpose>
       <refclass>Function</refclass>
     </refnamediv>
     <refsect1>
       <title>Syntax</title>
       <synopsis>
-      <function> (DROP-VIEW-FROM-CLASS VIEW-CLASS-NAME &amp;KEY (DATABASE *DEFAULT-DATABASE*)) [function]</function> => <returnvalue><!-- result --></returnvalue></synopsis>
+      <function>drop-view-from-class</function> <replaceable>view-class-name</replaceable> &amp;key <replaceable>database</replaceable> => <returnvalue><!-- result --></returnvalue></synopsis>
     </refsect1>
     <refsect1>
       <title>Arguments and Values</title>
       <variablelist>
-        <!-- arguments and values --> 
+       <varlistentry>
+         <term><parameter>view-class-name</parameter></term>
+         <listitem>
+           <para>
+             The name of the <glossterm linkend="gloss-view-class">View
+             Class</glossterm>.
+           </para>
+         </listitem>
+       </varlistentry>
+        <varlistentry>
+          <term><parameter>database</parameter></term>
+          <listitem>
+            <para>
+              <glossterm linkend="gloss-database-object">database
+              object</glossterm>. This will default to the value of
+              <symbol>*default-database*</symbol>.
+           </para>
+         </listitem>
+       </varlistentry>
       </variablelist>
     </refsect1>
     <refsect1>
       <title>Description</title>
-      <para>Removes a table defined by the View Class
-      VIEW-CLASS-NAME from DATABASE which defaults to
-      *DEFAULT-DATABASE*.
+      <para>Removes a table defined by the <glossterm
+      linkend="gloss-view-class">View Class</glossterm>
+      <parameter>view-class-name</parameter> from
+      <parameter>database</parameter> which defaults to
+      <parameter>*default-database*</parameter>.
       </para>
     </refsect1>
     <refsect1>
       <title>Examples</title>
       <screen>
-        <!-- examples -->
+(list-tables)
+=> ("FOO" "BAR")       
+(drop-view-from-class 'foo)
+=> 
+(list-tables)
+=> ("BAR")     
       </screen>
     </refsect1>
     <refsect1>
       <title>Side Effects</title>
       <para>
-        <!-- side effects --> 
+       Deletes a table from the SQL database.
       </para>
     </refsect1>
     <refsect1>
       <title>Affected by</title>
       <para>
-        <simplelist>
-          <!-- affected by --> 
-        </simplelist>
+       Whether the specified table exists in the SQL database.
       </para>
     </refsect1>
     <refsect1>
       <title>Exceptional Situations</title>
       <para>
-        <!-- execeptional situations -->
+       A condition may be signalled if the table does not exist in
+       the SQL database or if the SQL connection does not have
+       sufficient permissions to delete tables.
       </para>
     </refsect1>
     <refsect1>
       <title>See Also</title>
       <para>
-        <simplelist>
-          <!-- see also --> 
-        </simplelist>
+       <simplelist>
+         <member><link linkend="create-view-from-class"><function>create-view-from-class</function></link></member>
+         <member><link linkend="def-view-class"><function>def-view-class</function></link></member>
+       </simplelist>
       </para>
     </refsect1>
     <refsect1>
       <title>Notes</title>
       <para>
-        <!-- notes --> 
+        None. 
       </para>
     </refsect1>
   </refentry>
   <refentry id="list-classes">
     <refnamediv>
       <refname>LIST-CLASSES</refname>
-      <refpurpose><!-- purpose --></refpurpose>
+      <refpurpose>List classes for tables in SQL database.</refpurpose>
       <refclass>Function</refclass>
     </refnamediv>
     <refsect1>
       <title>Syntax</title>
       <synopsis>
-      <function> (LIST-CLASSES &amp;KEY (TEST #'IDENTITY) (ROOT-CLASS (FIND-CLASS 'STANDARD-DB-OBJECT)) (DATABASE *DEFAULT-DATABASE*)) [function]</function> => <returnvalue><!-- result --></returnvalue></synopsis>
+      <function>list-classes</function> &amp;key <replaceable>test</replaceable> <replaceable>root-class</replaceable> <replaceable>database</replaceable> => <returnvalue>classes</returnvalue></synopsis>
     </refsect1>
     <refsect1>
       <title>Arguments and Values</title>
       <variablelist>
-        <!-- arguments and values --> 
+       <varlistentry>
+         <term><parameter>test</parameter></term>
+         <listitem>
+           <para>
+             a function used to filter the search. By default, <parameter>identity</parameter> is used which
+             will return all classes.
+           </para>
+         </listitem>
+       </varlistentry>
+       <varlistentry>
+         <term><parameter>root-class</parameter></term>
+         <listitem>
+           <para>
+             specifies the root class to the search. By default,
+             <parameter>standard-db-object</parameter> is used which
+             is the root for all view classes.
+           </para>
+         </listitem>
+       </varlistentry>
+       <varlistentry>
+         <term><parameter>database</parameter></term>
+         <listitem>
+           <para>
+             The <glossterm
+             linkend="gloss-database-object">database</glossterm> to
+             search for view classes. This will default to the value
+             of <symbol>*default-database*</symbol>.
+           </para>
+         </listitem>
+       </varlistentry>
+       <varlistentry>
+         <term><parameter>classes</parameter></term>
+         <listitem>
+           <para>
+             List of view classes.
+           </para>
+         </listitem>
+       </varlistentry>
       </variablelist>
     </refsect1>
     <refsect1>
       <title>Description</title>
-      <para>Returns a list of all the View Classes which
-      are connected to DATABASE, which defaults to
-      *DEFAULT-DATABASE*, and which descend from the class
-      ROOT-CLASS and which satisfy the function TEST. By
-      default ROOT-CLASS is STANDARD-DB-OBJECT and TEST is
-      IDENTITY.
+      <para>Returns a list of all the View Classes which have been
+      defined in the Lisp session and are connected to
+      <parameter>database</parameter> and which descended from the
+      class <parameter>root-class</parameter> and which satisfy the
+      function <parameter>test</parameter>.
       </para>
     </refsect1>
     <refsect1>
       <title>Examples</title>
       <screen>
-        <!-- examples -->
+(list-classes)
+=> (#&lt;clsql-sys::standard-db-class big> #&lt;clsql-sys::standard-db-class employee-address>
+    #&lt;clsql-sys::standard-db-class address> #&lt;clsql-sys::standard-db-class company> 
+    #&lt;clsql-sys::standard-db-class employee>)
+
+(list-classes :test #'(lambda (c) (> (length (symbol-name (class-name c))) 3)))
+=> (#&lt;clsql-sys::standard-db-class employee-address> #&lt;clsql-sys::standard-db-class address>
+    #&lt;clsql-sys::standard-db-class company> #&lt;clsql-sys::standard-db-class employee>)
       </screen>
     </refsect1>
     <refsect1>
       <title>Side Effects</title>
       <para>
-        <!-- side effects --> 
+       None.
       </para>
     </refsect1>
     <refsect1>
       <title>Affected by</title>
       <para>
-        <simplelist>
-          <!-- affected by --> 
-        </simplelist>
+       <simplelist>
+         <member>Which view classes have been defined in the Lisp
+         session.</member>
+       </simplelist>
       </para>
     </refsect1>
     <refsect1>
       <title>Exceptional Situations</title>
       <para>
-        <!-- execeptional situations -->
+       None.
       </para>
     </refsect1>
     <refsect1>
       <title>See Also</title>
       <para>
-        <simplelist>
-          <!-- see also --> 
-        </simplelist>
+       <simplelist>
+         <member><link linkend="def-view-class"><function>def-view-class</function></link></member>
+       </simplelist>
       </para>
     </refsect1>
     <refsect1>
       <title>Notes</title>
       <para>
-        <!-- notes --> 
+        None. 
       </para>
     </refsect1>
   </refentry>
 
 
-
-
 </reference>